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  #1   Report Post  
Martin Evans
 
Posts: n/a
Default New condensing boiler installation - truth or lies

I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler
o water tank in loft feeding central heating
o one room thermostat in hall
o most (not all) radiators with TRVs - radiator in hall where room
thermostat is located does have a TRV.
o newish (3 years) programmable controller with separate CH and HW
settings and 1 hour, overrides.
o relatively new (3 years) myson cp53 pump.

During the conversation he told me:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.

2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.

3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.

4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.

5. Our gas meter was not earthed and so they would have to earth it
all. I'm not this is true since I remember a large earthing strap
behind the gas meter where the pipes come into the house - I cannot
investigate this now.

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.

7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.

8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.

9. It was around 3 days work.

10. the quote left has a "the effects of pluming have been explained"
but they never were.

11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex - and told me a horror
story about a house fire near us caused by wrong electrical
installation where the insurers were not fully paying out after
identifying sub standard electrical fitment of halogen lighting.

12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).

Needless to say I was less than impressed but then came the:

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):

British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31
radiator valves (15mm angled W/H & L/S) 26
Now he has left I don't understand this as we never spoke about
adding radiators or valves.
controls pack (2*22mm 2Port) Prog. (UP1) 307
convert to fully pumped 22mm (5mtr head) 312
powerlush - 195
install ME bonding 112
exectrical and mechanical supp bonding 79

there was other stuff like waster disposal, pipe insulation, fit pipe
insulation etc.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?

Martin
--
Martin J. Evans
Wetherby, UK
  #2   Report Post  
BigWallop
 
Posts: n/a
Default


"Martin Evans" wrote in message
...
I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler

snipped
Martin J. Evans
Wetherby, UK


What type of guarantees do you get with all this? Are they also providing
break-down cover for the first X amount of years on the whole installation?

Have you checked out the price of the boiler on the web?


  #3   Report Post  
Tony Bryer
 
Posts: n/a
Default

In article , Martin Evans
wrote:
British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31

I was somewhat surprised by the size of the quote and the cost of the
boiler


I think that we may presume from the above that he's proposing a
rebadged Glow-worm. A Glow-worm 30Hxi is 795 including VAT at

http://www.discountheating.com/wallc...lgas/30hxi.htm

Whether you need 213 of flue extensions is doubtful

- seemed pricey to me.


Seems typical BG gas price to regular readers here

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm
[Latest version QSEDBUK 1.10 released 4 April 2005]


  #4   Report Post  
Martin Evans
 
Posts: n/a
Default

On Fri, 17 Jun 2005 14:38:36 GMT, "BigWallop"
wrote:


"Martin Evans" wrote in message
.. .
I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler

snipped
Martin J. Evans
Wetherby, UK


What type of guarantees do you get with all this? Are they also providing
break-down cover for the first X amount of years on the whole installation?


I think he said 3 years included but I can't find that info in the
quote.

Have you checked out the price of the boiler on the web?


The boiler is exclusive to British Gas - The British Gas 330, so I
can't find it elsewhere - unless someone else knows better.

Martin
--
Martin J. Evans
Wetherby, UK
  #5   Report Post  
Christian McArdle
 
Posts: n/a
Default

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.


Well, there are exceptions, but these are unlikely to apply to you,.

2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.


You need a "boiler interlock" that completely turns off the boiler when the
house is hot. Normally this is supplied by the room thermostat. If there is
none, another method must be used, such as a flow switch on the heating
circuit. Did the installer indicate how boiler interlock was intended to be
achieved?

3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.


Without knowing all the boilers they supply, it isn't possible to say. Some
boilers have internal bypass, some don't. However, there's no reason to
disbelieve, really. You'd need one even without all TRV, as you are going
S-Plan.

4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.


Sounds normal, assuming the move around the corner is to improve aesthetics,
or flue location.

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.


Sounds good. Better than some where they use a "soak away", which is a
euphemism for sticking a bare pipe out of the wall which rots away your
patio.

7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.


The vertical height of the boiler and cylinder is no longer relevent, as the
system MUST be converted to fully pumped by law. Fully pumped systems don't
care about heights.

8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.


There are other methods, but the 2 valves and the pump is one of the most
common, simplest and reliable. It is called 'S' Plan. Some of the conversion
will be to make it a sealed pressurised system, rather than gravity fed.
This is well worth doing.

9. It was around 3 days work.


Could well be.

10. the quote left has a "the effects of pluming have been explained"
but they never were.


The exhaust terminal will shoot out loads of visible steam, especially in
winter. This may seriously annoy the neighbours, even though the exhaust is
actually cleaner and less poisonous that the invisible plume of older
boilers.

11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex


There is no need for the cabling to be flex. Indeed, apart from the final
connections to any immersion heaters, external pumps or zone valves, fixed
T&E wiring is actually superior. Flex is often used because it is easy to
get multicore versions which are more convenient, though.

- and told me a horror story about a house fire near us caused by
wrong electrical installation where the insurers were not fully
paying out after identifying sub standard electrical fitment of
halogen lighting.


Ignore friend of a friend horror stories. Almost certainly not true.

12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).


He is actually correct. Most modern condensing boilers have a much greater
maximum output than any normal house requires. (Some manufacturers have
recently produced throttled back versions that might struggle on a big
house, though). You need to have a 10 bedroom 1660s place with no glass in
the windows to exceed the capability. (Well not, quite, but if the
calculation did show a bigger boiler was needed, the correct approach is to
fix the house insulation, not fit a bigger boiler).

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):


Not actually that bad for a BG quote. Still much higher than a good local
engineer, but not in their normal stratispheric regions, given that the
quote includes lots of additional work to the actual boiler swap, such as
the fully pumped version, movement of the boiler, updating of controls etc.

glow-worm Xi std horizontal flue (800mm) 154


The Glowworm HXI/CXi/SXi is the boiler that is currently rescuing Glowworm's
reputation. It is certainly not scraping the barrel by going for a cheap
boiler.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.


Well, BG always give the most expensive quote. Make sure you phone round
some local non-chain places.

Christian.




  #6   Report Post  
EricP
 
Posts: n/a
Default

On Fri, 17 Jun 2005 14:25:01 GMT, Martin Evans
babbled like a waterfall and said:

I've had a British Gas man around today to quote for a new condensing
boiler.
I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?

Martin


Yes, been down the same amusing road. Get anybody else to quote and
you should knock 1000 off the job. Get three people to quote and you
should arrive at a fair price.
Put the BG stuff in the bin.

  #7   Report Post  
Martin Evans
 
Posts: n/a
Default

On Fri, 17 Jun 2005 15:50:40 +0100, Tony Bryer
wrote:

In article , Martin Evans
wrote:
British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31

I was somewhat surprised by the size of the quote and the cost of the
boiler


I think that we may presume from the above that he's proposing a
rebadged Glow-worm. A Glow-worm 30Hxi is 795 including VAT at

http://www.discountheating.com/wallc...lgas/30hxi.htm


Thanks for that - it helps to know what the boiler might be. All I
have is some marketing stuff from BG telling me how good it is. SEDBUK
A rated, NOX class 5 emissions, SS heat exchanger, on board
diagnostics, "Continua" electronics allowing the boiler to continue
where others may fail (hmm), adjustable for my future radiator needs,
frost protection.

Whether you need 213 of flue extensions is doubtful


I didn't get that either. The boiler is only moving round an inside
corner so it will be less than 0.5m from the outside wall and 213 +
VAT for flue extensions seemed rediculous.

- seemed pricey to me.


Seems typical BG gas price to regular readers here


Thanks for th response.

Martin
--
Martin J. Evans
Wetherby, UK
  #8   Report Post  
Martin Evans
 
Posts: n/a
Default

Chistian,

Thanks for the info.

On Fri, 17 Jun 2005 16:34:30 +0100, "Christian McArdle"
wrote:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.


Well, there are exceptions, but these are unlikely to apply to you,.


So I gather. It would be really difficult to argue in my case.

2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.


You need a "boiler interlock" that completely turns off the boiler when the
house is hot. Normally this is supplied by the room thermostat. If there is
none, another method must be used, such as a flow switch on the heating
circuit. Did the installer indicate how boiler interlock was intended to be
achieved?


Not that I recall. A question I'll ask of him.

3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.


Without knowing all the boilers they supply, it isn't possible to say. Some
boilers have internal bypass, some don't. However, there's no reason to
disbelieve, really. You'd need one even without all TRV, as you are going
S-Plan.

4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.


Sounds normal, assuming the move around the corner is to improve aesthetics,
or flue location.


Actually moving it round the corner increases flue length. The problem
occurs because the current boiler is on an end wall right up to a
boxed vertical section carrying the soil pipe, other pipes and pump.
On the other side of the corner my wife wants two double wardrobes and
if the boiler was replaced in the current position there would only be
29cm space in front of the bolier. He suggested putting the boiler on
the wall to carry the wardrobes inside one of them. I assumed the
corner flue piece he quoted for was to take the flue round to the
existing flue exit hole which is why I was also questioning the
"specialist building work".

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.


Sounds good. Better than some where they use a "soak away", which is a
euphemism for sticking a bare pipe out of the wall which rots away your
patio.

7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.


The vertical height of the boiler and cylinder is no longer relevent, as the
system MUST be converted to fully pumped by law. Fully pumped systems don't
care about heights.


He didn't explain it must be converted to fully pumped he made it
sound like our system was wrong and the new one would overcome this
error.

8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.


There are other methods, but the 2 valves and the pump is one of the most
common, simplest and reliable. It is called 'S' Plan. Some of the conversion
will be to make it a sealed pressurised system, rather than gravity fed.
This is well worth doing.


I think this is where this "air vent thingy" come in - it was
something to do with keeping our system open. He definitely said they
would not be converting it to sealed system because some of the
pipework is in concrete and a leak would be a big problem.

9. It was around 3 days work.


Could well be.

10. the quote left has a "the effects of pluming have been explained"
but they never were.


The exhaust terminal will shoot out loads of visible steam, especially in
winter. This may seriously annoy the neighbours, even though the exhaust is
actually cleaner and less poisonous that the invisible plume of older
boilers.


"shoot out" does not sound so good. It is less than 3' to a fence and
then less than 3' to my neighbours house with the fence lower than the
vent. Shooting out whilst someone is walking down the side of the
house (either on my side or my neighbours) wouldn't be good.

11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex


There is no need for the cabling to be flex. Indeed, apart from the final
connections to any immersion heaters, external pumps or zone valves, fixed
T&E wiring is actually superior. Flex is often used because it is easy to
get multicore versions which are more convenient, though.


The valve behind the cylinder is connected to a junction box by T&E.
From here 2 T&E come down to another juntion box where flex goes off
to the boiler and programmer. The immersion heater is flex. It was the
T&E down the boxed section from my airing cupboard to the jn box below
he specifically tutted at.

- and told me a horror story about a house fire near us caused by
wrong electrical installation where the insurers were not fully
paying out after identifying sub standard electrical fitment of
halogen lighting.


Ignore friend of a friend horror stories. Almost certainly not true.

12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).


He is actually correct. Most modern condensing boilers have a much greater
maximum output than any normal house requires. (Some manufacturers have
recently produced throttled back versions that might struggle on a big
house, though). You need to have a 10 bedroom 1660s place with no glass in
the windows to exceed the capability. (Well not, quite, but if the
calculation did show a bigger boiler was needed, the correct approach is to
fix the house insulation, not fit a bigger boiler).


That is very good to know. This one worried me the most.

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):


Not actually that bad for a BG quote. Still much higher than a good local
engineer, but not in their normal stratispheric regions, given that the
quote includes lots of additional work to the actual boiler swap, such as
the fully pumped version, movement of the boiler, updating of controls etc.

glow-worm Xi std horizontal flue (800mm) 154


The Glowworm HXI/CXi/SXi is the boiler that is currently rescuing Glowworm's
reputation. It is certainly not scraping the barrel by going for a cheap
boiler.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.


Well, BG always give the most expensive quote. Make sure you phone round
some local non-chain places.


Have done so.

Thanks again. Your post has helped sort a few things out for me.

Martin
--
Martin J. Evans
Wetherby, UK
  #9   Report Post  
Andy Hall
 
Posts: n/a
Default

On Fri, 17 Jun 2005 14:25:01 GMT, Martin Evans
wrote:

I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler
o water tank in loft feeding central heating
o one room thermostat in hall
o most (not all) radiators with TRVs - radiator in hall where room
thermostat is located does have a TRV.
o newish (3 years) programmable controller with separate CH and HW
settings and 1 hour, overrides.
o relatively new (3 years) myson cp53 pump.

During the conversation he told me:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.


Generally this is the case. There is a system for exceptions based on
location and work involved to site a condensing boiler which applies
points to a number of difficulty issues. However, if it is a
replacement for an existing wall mount boiler then you are unlikely to
meet the exclusion criteria.




2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.


There has to be a means of locking out the boiler when the heating for
the house is satisfied and this normally does mean a room thermostat.
It should not be in a room containing radiators with TRVs because the
two will tend to fight. The correct solution is to remove the TRVs
not the room thermostat, although the latter could probably usefully
be changed to an electronic optimising type.



3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.


Many do, and possibly all the ones that they sell, but I am not sure
that this is universally the case. The manufacturer installation
instructions will specify whether a bypass is needed or not.




4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.


The manufacturer's installation instructions are the definitive source
of space requirements.



5. Our gas meter was not earthed and so they would have to earth it
all. I'm not this is true since I remember a large earthing strap
behind the gas meter where the pipes come into the house - I cannot
investigate this now.


There should be electrical bonding from the meter to the main earthing
point in the house. The gas supply should not be used as the
electrical earth.


6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.


Correct. It needs some from of suitable entry into it, though.



7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.


If the existing system is using "gravity" circulation to heat the HW
cylinder then the vertical vs. horizontal pipe runs can matter.
However, modern boilers, expecially in a new system like this are used
fully pumped so it doesn't matter.




8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.


Waffle. It might be worth installing a new fast recovery cylinder to
make the most of the pumped arrangement.




9. It was around 3 days work.


Could be.


10. the quote left has a "the effects of pluming have been explained"
but they never were.


You may get a plume of water vapour from the boiler flue under certain
conditions. These are typically most noticable when the boiler runs
flat out on a cold day. If the flue is facing the neighbour's
boundary and is close to it, then this may be an issue. However there
are flue types for some boilers that can be routed over several metres
and can exit in a completely different place. Some can even be 50mm
high temperature waste pipe. Of course BG might not have these on
their list.





11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex - and told me a horror
story about a house fire near us caused by wrong electrical
installation where the insurers were not fully paying out after
identifying sub standard electrical fitment of halogen lighting.


Possibly. Certain cables should be flexible types. However, the way
it's described sounds more like FUD to justify higher quote.



12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).


To an extent that's true. If the current boiler is adequately heating
the house, then fitting one having somewhat more capacity is fine.
They do modulate their output over a wide range.




Needless to say I was less than impressed but then came the:

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):

British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31
radiator valves (15mm angled W/H & L/S) 26
Now he has left I don't understand this as we never spoke about
adding radiators or valves.
controls pack (2*22mm 2Port) Prog. (UP1) 307
convert to fully pumped 22mm (5mtr head) 312
powerlush - 195
install ME bonding 112
exectrical and mechanical supp bonding 79

there was other stuff like waster disposal, pipe insulation, fit pipe
insulation etc.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?

It is a high quote for this. It doesn't really matter how they've
carved it up, the overall price is what is important.
I would have thought that 2000 was nearer to a reasonable target for
a good boiler and the works described - more if you change the
cylinder, and I would suggest that, because the water will re-heat
faster and the boiler can return to heating the house sooner. With
most control arrangements, the HW has priority over the CH, so you
really want to heat the water quickly (it is more efficient if you can
transfer a lot of heat quickly) and then return to CH.





--

..andy

To email, substitute .nospam with .gl

The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
http://www.diybanter.com

  #10   Report Post  
John Rumm
 
Posts: n/a
Default

Martin Evans wrote:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.


Mostly true... from the sounds of your setup it is not worth worrying
about the possible get out clauses.

2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.


Personally I would change the room stat to a programmable one and remove
the TRV. You still need some form of interlock to shut off the boiler
when the whole house is warm.

3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.


Could well be true for theirs...

4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.


Just so you can get the case off basically. Can you not do that in the
current location?

5. Our gas meter was not earthed and so they would have to earth it
all. I'm not this is true since I remember a large earthing strap
behind the gas meter where the pipes come into the house - I cannot
investigate this now.


The service bonding ought to be done on the consumer side of the meter
rather than the supply as used to be the case.

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.

7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.


This sounds like he is confusing a bit of old gravity fed sales
patter... for a fully pumped setup it will make no difference.

It might be worth investigating a new fast recovery cylinder however. If
you current one is old, remember the things don't last forever. A fast
recovery one will also be able to swallow more of the boilers output.
THe modulating function of the boiler however ought to prevent cycling
anyway.

8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.

9. It was around 3 days work.


Sounds plausable - depending on what pipework needs doing. Took me about
4 days, but that included stripping out all the old tanks as well.

10. the quote left has a "the effects of pluming have been explained"
but they never were.


Like Christain said...

11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex - and told me a horror
story about a house fire near us caused by wrong electrical
installation where the insurers were not fully paying out after
identifying sub standard electrical fitment of halogen lighting.


You can ignore that I would guess.

12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).


Since you are not looking at a combi where the output power will
directly dictate your hot water flow rate, it is less of an issue. As
long as you have "enough" the modulation will make a decent job of
matching the actual output to the demand. It is sometimes more useful to
ask what the lowest power output of the boiler is. Ones that can
modulate right down to 4 or 5kW being better than ones that only go down
to say 12.

Needless to say I was less than impressed but then came the:

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):


For BG that sounds cheap... 5.5 would be closer to their normal!

British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559


Probably fair for the boiler on its own...

specialist building work (3) 174


But you would expect this to be included in the above...

can't imagine what this was other than repositioning flue
connect boiler electrics and test 64


and this

glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31


probably don't need those - especially if you keep it in the current
location.

radiator valves (15mm angled W/H & L/S) 26
Now he has left I don't understand this as we never spoke about
adding radiators or valves.


He may be talking about replacing the old lockshied valves with new
ones. Some of the older ones can weep when converted to pressurised
operation.

controls pack (2*22mm 2Port) Prog. (UP1) 307


Sounds a bit much...

convert to fully pumped 22mm (5mtr head) 312


hmmmm...

powerlush - 195


perhaps

install ME bonding 112


excessive...

exectrical and mechanical supp bonding 79


excessive...

there was other stuff like waster disposal, pipe insulation, fit pipe
insulation etc.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?


I would have thought something closer to 2k would be more like it....


--
Cheers,

John.

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  #11   Report Post  
Ed Sirett
 
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On Fri, 17 Jun 2005 14:25:01 +0000, Martin Evans wrote:

I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler
o water tank in loft feeding central heating
o one room thermostat in hall
o most (not all) radiators with TRVs - radiator in hall where room
thermostat is located does have a TRV.
o newish (3 years) programmable controller with separate CH and HW
settings and 1 hour, overrides.
o relatively new (3 years) myson cp53 pump.

During the conversation he told me:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.

Almost certainly true.


2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.

If the wall stat is in a good place then the TRV should go.
A good place for a wall stat:
a) Not subject direct heat (from sunlight, radiator, or other source of
heat).
b) In a room that is representative of the heating as a whole.
(i.e not in cooler rooms/ bedrooms/ bathrooms).
c) Not in a room with an additional source of heat (not in kitchen or
living room with fire)

This invariably makes the hallway and maybe the living room the best
places.


3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.

They are fitting something modern , so likely true.
There is no easy way to go all TRV and comply with Part L.


4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.


Find out the model, download the instructions and decide for yourself -
it's likely true.



5. Our gas meter was not earthed and so they would have to earth it
all. I'm not this is true since I remember a large earthing strap
behind the gas meter where the pipes come into the house - I cannot
investigate this now.

The correct place is on the first 600mm of outlet (your) pipework.

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.


Dropping the condensate into the soil pipe is acceptable.



7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.

OK this is the first one I'm unhappy about. The HW cylinder must (same
'must' as q1) be a fastish recovery unit (less than 25mins from cold
IIRC). Such a cylinder will likely be able to take the bulk of the
boiler's output.
In my own home a cylinder reheat cycle take c. 10mins this consists of
60seconds of 25kW follwed by c. 10 min of ever reducing power output till
the cylinder stat call time.
The cylinder is adjacent to the boiler and is about 1m there and 1m back
as the Irish say.



8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.

True. True. True. But any good heating engineer is going to recommend the
same. Pump is likely in the boiler.


9. It was around 3 days work.

True. for 2 experienced guys.



10. the quote left has a "the effects of pluming have been explained"
but they never were.


So they messed up.


11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex - and told me a horror
story about a house fire near us caused by wrong electrical
installation where the insurers were not fully paying out after
identifying sub standard electrical fitment of halogen lighting.

Maybe so.
However, I thought that by the book the wiring for heating controls
should be in cable with flex outlets adjacent to each sensor/appliance.
Usually they are just done in flex throughout . Cable _is_ incorrect.


12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).


OK On the [mandatory spit] C&G energy course some of us locked horns
with the tutor on this one. I maintained that the _first_ question to ask
was "How well did the heating work [before it broke!]" and this along with
experience and further questions like "Was there anywhere always too hot
or always cold". _Then_ you could run through the calculations to see if
you need to size up or down a bit (or even a lot).

The tutor maintained that you run through the standard assessment calcs
then size the boiler and ignore the existing installation (what utter
********).

It is true that modern boilers are considerably more forgiving of being
over-sized than older models.

The BG guy here is plain wrong and would fail a C&G assessment.



Needless to say I was less than impressed but then came the:

Total quote was for 3498 including VAT (and 100 trade in discount)

7 with some significant numbers being (not including VAT):

British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31
radiator valves (15mm angled W/H & L/S) 26
Now he has left I don't understand this as we never spoke about
adding radiators or valves.
controls pack (2*22mm 2Port) Prog. (UP1) 307
convert to fully pumped 22mm (5mtr head) 312
powerlush - 195
install ME bonding 112
exectrical and mechanical supp bonding 79

there was other stuff like waster disposal, pipe insulation, fit pipe
insulation etc.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?


An independent fitter if you can get hold of one should be around 2250
give or take. They are Fleecing it heavy on the controls. I'm nigh on sure
you can buy the whole lot for just over 100 (on a bad day).

I can't be bothered to look up the boiler on the net but I'd be surprised
if it's much over 700 + VAT.

The 'advanced' controls are subject to reduced VAT (5% IIRC) which is just
tokenism on the part of the treasury, IMHO.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html


  #12   Report Post  
Ed Sirett
 
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On Fri, 17 Jun 2005 17:28:42 +0100, John Rumm wrote:

Martin Evans wrote:


Having read through the other posts (no one's drivelling IMHO) and your
further comments.

It seems that BG are doing two things which I had not realized.

1) They are not going to a sealed system - they are obviously concerned
about the state of the pipework in the concrete floor. They are being
cautious; if and only if the existing pipework is working correctly and
never pumps over and never entrains air then I think on balance they are
right. Without seeing the job it's hard to balance the risks.

2) They are _illegally_ not intending to upgrade the water cylinder this
is in contravention of the Building Regs. ISTM that the quotation
operative from BG is not up top speed on the current regs.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html


  #13   Report Post  
Owain
 
Posts: n/a
Default

Martin Evans wrote:
Christian McArdle wrote:
10. the quote left has a "the effects of pluming have been explained"
but they never were.

The exhaust terminal will shoot out loads of visible steam,

"shoot out" does not sound so good. It is less than 3' to a fence and
then less than 3' to my neighbours house with the fence lower than the
vent. Shooting out whilst someone is walking down the side of the
house (either on my side or my neighbours) wouldn't be good.


Isn't it water vapour, rather than steam? I think it's quite pretty,
especially on a frosty day.

I don't think - although I could be wrong - the flue gets dangerously
hot. AFAIK it's acceptable to have the flue somewhere someone walks past
provided there's a wire cage over it to prevent direct contact.

What must be carefully positioned is the pressure relief outlet, which
shouldn't shoot out anything in normal circumstances, but will shoot out
boiling water and/or steam if Something Goes Wrong.

Owain

  #14   Report Post  
John Rumm
 
Posts: n/a
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Owain wrote:

Isn't it water vapour, rather than steam? I think it's quite pretty,
especially on a frosty day.

I don't think - although I could be wrong - the flue gets dangerously
hot. AFAIK it's acceptable to have the flue somewhere someone walks past
provided there's a wire cage over it to prevent direct contact.


The flue gas temperature will be significantly lower than with a
conventional boiler. So it is better to get hit by the output from a
condensor than a conventional boiler. The only real difference is it is
cold enough for the water vapour to be visible.




--
Cheers,

John.

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| John Rumm - john(at)internode(dot)co(dot)uk |
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  #15   Report Post  
John
 
Posts: n/a
Default


"Owain" wrote in message
.. .
Martin Evans wrote:
Christian McArdle wrote:
10. the quote left has a "the effects of pluming have been explained"
but they never were.
The exhaust terminal will shoot out loads of visible steam,

"shoot out" does not sound so good. It is less than 3' to a fence and
then less than 3' to my neighbours house with the fence lower than the
vent. Shooting out whilst someone is walking down the side of the
house (either on my side or my neighbours) wouldn't be good.


Isn't it water vapour, rather than steam? I think it's quite pretty,
especially on a frosty day.


Steam is actually invisible (and highly dangerous as a result).

Glow worm have recognised the plume as being a problem and make a kit to
extend the discharge upwards and away from the flue wall exit point.

I don't think - although I could be wrong - the flue gets dangerously hot.
AFAIK it's acceptable to have the flue somewhere someone walks past
provided there's a wire cage over it to prevent direct contact.


The cage is a throwback to flue terminals which got hot enough to brand you.
A cage was to stop this happening so as a result you got a criss-cross wire
pattern burnt into your flesh as a resultg
The requirement is still included in the GSIUR of course


What must be carefully positioned is the pressure relief outlet, which
shouldn't shoot out anything in normal circumstances, but will shoot out
boiling water and/or steam if Something Goes Wrong.


True




  #16   Report Post  
John Rumm
 
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John wrote:

Glow worm have recognised the plume as being a problem and make a kit to
extend the discharge upwards and away from the flue wall exit point.


I find it supprising that people get so upset at the sight of a bit of
water vapour... They must get really scared when they make a cup of tea! ;-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #17   Report Post  
Andrew Gabriel
 
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In article ,
"John" writes:

"Owain" wrote in message
.. .

Isn't it water vapour, rather than steam? I think it's quite pretty,
especially on a frosty day.


Steam is actually invisible (and highly dangerous as a result).


Yes. The plume is actually a fog -- tiny condensed water droplets
suspended in air. Steam is invisible, but often forms a fog at the
boundary where it mixes with colder air. A condensing boiler should
not be emitting any steam -- the flue gases aren't hot enough (even
when it's not operating in condensing mode).

Glow worm have recognised the plume as being a problem and make a kit to
extend the discharge upwards and away from the flue wall exit point.

I don't think - although I could be wrong - the flue gets dangerously hot.
AFAIK it's acceptable to have the flue somewhere someone walks past
provided there's a wire cage over it to prevent direct contact.


The cage is a throwback to flue terminals which got hot enough to brand you.
A cage was to stop this happening so as a result you got a criss-cross wire
pattern burnt into your flesh as a resultg
The requirement is still included in the GSIUR of course


Likewise, required clearances below plastic drain pipes made
me smile, when the flue itself is a plastic drain pipe;-)
I had to go through the rather pointless task of moving the
rainwater pipework when I installed mine.

--
Andrew Gabriel
  #18   Report Post  
Andy Hall
 
Posts: n/a
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On Sat, 18 Jun 2005 14:08:32 +0100, wrote:

On 18 Jun,
John Rumm wrote:

John wrote:

Glow worm have recognised the plume as being a problem and make a kit to
extend the discharge upwards and away from the flue wall exit point.


I find it supprising that people get so upset at the sight of a bit of
water vapour... They must get really scared when they make a cup of tea! ;-


What I wonder about condensing boilers is whether the low temprerature plume
can spread legionella. Can water sit anywhere at a suitable temperature to
allow growth of the bug. What precautions need to be taken to prevent this.


Several points.

- In the area of the burner the temperatures are considerably higher.

- Flues are normally arranged with a slight slope back towards the
boiler for nominally horizontal runs so that water condensing in the
flue goes mainly back into the boiler. This is also to stop it
dripping out onto the ground outside.

- Internally in the boiler, there is an arrangement for the water to
run down into a trap from where it then drains out. Hence there is
not really a place where it will remain stationary for long.

- The condensate water is mildly acidic.

- Condensing boiler technology has been in use elsewhere in Europe for
20 years and there are not large outbreaks of Legionella reported as a
result of its use.




--

..andy

To email, substitute .nospam with .gl

The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
http://www.diybanter.com

  #19   Report Post  
Andrew Gabriel
 
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In article ,
writes:

What I wonder about condensing boilers is whether the low temprerature plume
can spread legionella. Can water sit anywhere at a suitable temperature to
allow growth of the bug. What precautions need to be taken to prevent this.
Has a risk assessment been done?


My Keston, which ran at around 45C flow through most of the winter,
did manage to grow something a bit jellyfish like in the bottom of
the heat exchanger (which would have been slightly cooler than 45C).
This then blocked the condensate drain causing the heat exchanger
to start filling up until it was making quite a gurgling noise and
failed to light. I didn't conclusively prove if the jellyfish like
thing was animal, vegetable, or mineral and it was broken into
small pieces by the time I got it out.

--
Andrew Gabriel
  #20   Report Post  
Doctor Evil
 
Posts: n/a
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"Andy Hall" wrote in message
...
On Sat, 18 Jun 2005 14:08:32 +0100, wrote:

On 18 Jun,
John Rumm wrote:

John wrote:

Glow worm have recognised the plume as being a problem and make a kit

to
extend the discharge upwards and away from the flue wall exit point.

I find it supprising that people get so upset at the sight of a bit of
water vapour... They must get really scared when they make a cup of

tea! ;-

What I wonder about condensing boilers is whether the low temprerature

plume
can spread legionella. Can water sit anywhere at a suitable temperature

to
allow growth of the bug. What precautions need to be taken to prevent

this.

Several points.

- In the area of the burner the temperatures are considerably higher.

- Flues are normally arranged with a slight slope back towards the
boiler for nominally horizontal runs so that water condensing in the
flue goes mainly back into the boiler. This is also to stop it
dripping out onto the ground outside.

- Internally in the boiler, there is an arrangement for the water to
run down into a trap from where it then drains out. Hence there is
not really a place where it will remain stationary for long.

- The condensate water is mildly acidic.

- Condensing boiler technology has been in use elsewhere in Europe for
20 years


More like 40 years.




  #21   Report Post  
Doctor Evil
 
Posts: n/a
Default


"Owain" wrote in message
.. .
Martin Evans wrote:
Christian McArdle wrote:
10. the quote left has a "the effects of pluming have been explained"
but they never were.
The exhaust terminal will shoot out loads of visible steam,

"shoot out" does not sound so good. It is less than 3' to a fence and
then less than 3' to my neighbours house with the fence lower than the
vent. Shooting out whilst someone is walking down the side of the
house (either on my side or my neighbours) wouldn't be good.


Isn't it water vapour, rather than steam? I think it's quite pretty,
especially on a frosty day.


Divert the flue into a chimney stack. That really looks the part.



  #22   Report Post  
Martin Evans
 
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A huge thanks to all who replied to my post - many of the comments
have been useful in helping me understand some of the issues I had
with the visit by BG to look at upgrading my heating system.

This is a long post including an attempt at a summary of what I think
I've learnt. Hope it is useful to others as a illustration of my
confusions and the problems.

Since BG came to see me my wife found a local plumber and I had also
rung a local plumbing comany for a quote. I'm a little nearer a
decision but I think the old advice of always get 3 quotes has a big
draw back - you get a different story from each one. Not being an
expert in heating systems when I'm confronted with differing advice it
just lowers your confidence in any of it.

The differences in quotes and advice is vast including (if any are
reading I hope my summaries are accurate but if not I either
misunderstood or you did not explain it well enough):

o BG suggested keeping my existing system with what seems like a
rebadged Glow-worm 30Hxi (thanks Tony). Their quote as BigWallop
suggested includes effectively insurance on the new system components
and the rest of the remaining system for 3 years (or so I was led to
believe - no documentation on that). My shower pump stays so I keep a
good output from my shower but still have to put up with the noise
from it. Cost 3498 including VAT.

He did not mention possibility of a sealed system or combi boilers.

BG never left my old kitchen where my existing boiler is located, and
didn't ask to look at my water cylinder. He did have a laptop,
firewire printer and could print out a full quote including colour
marketing on the rebadged boiler though.

o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.

b) it would be cheaper to install than keeping my existing system as
it was far less components and mostly required ripping (bypassing)
existing system out rather than renewing/replacing. Basically, the
cold water tank would be bypassed, the cylinder goes, my shower pump
goes, electrics are trivial since all that is needed it something to
the boiler. I liked the sound of losing my shower pump IF the output
at the shower head was as good since the shower pump is noisy.

c) my gas supply to boiler was 15mm and needed to be 22mm. There is no
easy way to get a 22mm pipe from the 22mm pipe at the back of my meter
to the boiler but it could be run outside (around a 3m run) so long as
the pipe was held off the wall.

d) To check the new system would cope/match my existing shower pump I
needed to lookup the output from my pump (i've struggles with this as
the plate on it quote 3 l/min numbers). Also, I needed to check the
spec of the shower valve in my ensuite to ensure it was OK for the new
increased standing pressure.

e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height.

f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.

g) Mentioning some pipework in concrete floor he was unperturbed,
suggesting the increased pressure of my new sealed system was not that
high and if existing system was working I'd be OK.

h) I mentioned past experience of combi boilers (over 12 years ago)
and he said the worcester 440 was miles ahead of whatever I had then
and I would not suffer from excessive reduced flow in winter. He did
go on quite a bit about what temperature my shower ran at and how I
was mixing alot of cold water with hot to get confortable.

i) he said my existing cylinder (although only 5 years old) was not up
to spec since it did not have 2" of insulation (I might have the exact
number wrong).

j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.

k) the worcester 440 had an in built 12l (I think) vessel which had
some advantage in the speed in which hot water reached my taps - not
sure exactly.

Cost 2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system)
- sealed system.

o plumber number 2

quote not received yet but it was for a wall mounting Worcester 3XX
(something) 12l/min output at X degrees C rise (have not got the
brochure).

o concurred with plumber 1 than cylinder was not up to spec. Also said
the hot water feed to my shower pump was too high in the cylinder.
Also said the cylninder would be better turned through 90 degrees for
easier access to valve - fair enough.

o concurred with plumber 1 re TRV and room therm in same room.

o on business of 22mm gas feed to boiler - some needed it some don't -
often plumbers size up from 15 to 22 - a bit wishy washy - I was not
certain what was required but if a 22mm pipe was required as with
plumber 1 it could be run along outside wall.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.

o as with plumber 1 he'd need specs for ensuite shower valve as it
might not be up to increased standing pressure if we went combi boiler
but the myra shower valve in bathroom was certainly OK (I knew this
anyway as some tosser who previously installed shower in bathromm
before we moved here plumbed it in to the bath supply where the cold
water was mains pressure). When it leaked badly I needed to replace it
in a hurry and found I needed a more expensive valve to handle the
imbalance. Since then it has been replumbed to the cold tank.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did
not use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.

o servicing required for worcester 3XX was once every 12 to 18 months
and would cost around 50.

o room thermostat was required and they would not need to put cables
in as it was a (cableless) radio one.

o would quote for a powerflush at 395 which would take the best part
of a day as it involved connecting to heating system and flushing
through plus connecting to each radiator individually. When I
suggested this sounded alot (BG quoted 200) he said if the system had
been drained recently and was clean I could just ignore that in the
quote. They would have to drain the system twice anyway and lfush it
with some agent. He didn't try to sell it to me especially when I said
the system had been drained more than 5 times in the last 2 years
alone and drained out clean (also all of my radiators except one is
brand new).

o mains pressure was good in my area and not a worry.

o it cost them 5 to register the installation with Corgi who would
send me something I needed to keep as it would be required when I sold
my house.

o gas mains was being updated in my area since it fell off too much
(and caused some boilers to shut down) early in the morning when all
these new condensing boilers switched on.

What I think is a summary of the "true" bits of advice/information I
received from BG, local plumbers and this news group a

o you have to fit a condensing boiller unless you can amass 1000 pts
on a rather difficult to achieve scale. Certainly, a replacement
boiler is unlikey to achieve 1000 pts.

o plumning - I'm not going there - it seems a contentious issue.

o when moving to a condensing boiler you need a fully pumped system
(no gravity fed hot water) - this is law.

o don't have TRV on the radiator in the same room as a room thermostat
- also avoid rooms with other heat sources - kitchen, rooms with fires
etc Ed.

o condensing boilers produce condensate which is slightly acidic and
has to have somewhere to drain away.

o some boilers come with bypass valves, some don't. You can't go all
TRVs without a bypass valve.

o You need a "boiler interlock" that completely turns off the boiler
when the house is hot. Normally this is supplied by the room
thermostat. If there is none, another method must be used, such as a
flow switch on the heating circuit - thanks Christian/Andy/John.

o some condensing boilers are modulating so instead of a constant
power output they adjust to conditions. Minimum outout of boiler is
worht looking at.

o There should be electrical bonding from the meter to the main
earthing point in the house. The service bonding ought to be done on
the consumer side of the meter rather than the supply as used to be
the case.

o water cylinders are subject to building regs and upgrading a system
might (or must) mean upgrading the cylinder to current regs. Also, see
fast recovery cylinders (this was not mentioned to me by anyone
quoting).

On Fri, 17 Jun 2005 14:25:01 GMT, Martin Evans
wrote:

I've had a British Gas man around today to quote for a new condensing
boiler. My existing set up is:

o boiler - very old - over 25 years, wall mounted. Flue straight out
back to outside above head height (about 5-6ft to next doors house).
o gavity fed hot water with thermostat on tank, controlling valve
(motor currently broken so manually fixed open although I have a new
motor for it) and boiler
o water tank in loft feeding central heating
o one room thermostat in hall
o most (not all) radiators with TRVs - radiator in hall where room
thermostat is located does have a TRV.
o newish (3 years) programmable controller with separate CH and HW
settings and 1 hour, overrides.
o relatively new (3 years) myson cp53 pump.

During the conversation he told me:

1. it is against the law to not fit condensing boilers now.
From other postings this would seem true.

2. They would remove the room thermostat as it was bad to have it in a
room where radiators have TRVs.
Other posts to this group seem to suggest having a room thermo is OK
but not to have TRVs in the same room.

3. When I said I wasn't sure if we had a bypass and if we went all
TRVs I thought we'd need one he said all their condensing boilers come
with a built in bypass.

4. Regarding placement on the boiler he said manufacturer specs said
their must be at least 600mm space in front of the boiler although it
was OK in a cupboard so long as with the doors open their was 600mm in
front. As a result he suggested installing it around the corner from
where it is now.

5. Our gas meter was not earthed and so they would have to earth it
all. I'm not this is true since I remember a large earthing strap
behind the gas meter where the pipes come into the house - I cannot
investigate this now.

6. condensate from new boiler was not a problem since the boiler will
be sited next to a soil pipe.

7. our system was wrong be cause there is not at least 1.5m between
the top of the boiler and where the pipes go into the cylinder. This
would cause our boiler to switch on and off alot when only heating hot
water.

8. conversion from gravity fed to fully pumped was a time consuming
process. Some sort of air valve would have to be installed - I'm not
sure exactly about this. The system would have to be fully pumped
which mean installation ot 2 new valves and pump.

9. It was around 3 days work.

10. the quote left has a "the effects of pluming have been explained"
but they never were.

11. He criticised the current electrical installation a lot. Wrong
cable used throughout - should all be flex - and told me a horror
story about a house fire near us caused by wrong electrical
installation where the insurers were not fully paying out after
identifying sub standard electrical fitment of halogen lighting.

12. When I asked how he would calculate what size of boiler we'd need
he said he didn't need to as it would be a modulating condensing
boiler which constantly monitors the exit and return water temperature
and adjusts automatically. I did not think this was a satisfactory
answer since clearly if he fitted a 1KW boiler it would not sufficient
(absurd example I know).

Needless to say I was less than impressed but then came the:

Total quote was for 3498 including VAT (and 100 trade in discount)
with some significant numbers being (not including VAT):

British/Scottish Gas 330 HE Condensing Boilrer (inc labour and
installation) 1559
specialist building work (3) 174
can't imagine what this was other than repositioning flue
connect boiler electrics and test 64
glow-worm Xi std horizontal flue (800mm) 154
glow-worm Xi flue extension (500mm) 28
glow-worm Xi 90 flue elbow 31
radiator valves (15mm angled W/H & L/S) 26
Now he has left I don't understand this as we never spoke about
adding radiators or valves.
controls pack (2*22mm 2Port) Prog. (UP1) 307
convert to fully pumped 22mm (5mtr head) 312
powerlush - 195
install ME bonding 112
exectrical and mechanical supp bonding 79

there was other stuff like waster disposal, pipe insulation, fit pipe
insulation etc.

I was somewhat surprised by the size of the quote and the cost of the
boiler - seemed pricey to me.

Any useful comments?

Martin


--
Martin J. Evans
Wetherby, UK
  #23   Report Post  
Ed Sirett
 
Posts: n/a
Default

On Tue, 21 Jun 2005 21:14:29 +0000, Martin Evans wrote:



o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

I Maybe wrong but IIRC all Greenstar boilers are condensing.

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.


Initially before the store of HW in the boiler gives out this is likely
true. The usability of the system is likely to be good enough except for
high speed bath running.


b) it would be cheaper to install than keeping my existing system as
it was far less components and mostly required ripping (bypassing)
existing system out rather than renewing/replacing. Basically, the
cold water tank would be bypassed, the cylinder goes, my shower pump
goes, electrics are trivial since all that is needed it something to
the boiler. I liked the sound of losing my shower pump IF the output
at the shower head was as good since the shower pump is noisy.


A wall stat (preferrably programmable) will also be needed to comply with
current regs.


c) my gas supply to boiler was 15mm and needed to be 22mm. There is no
easy way to get a 22mm pipe from the 22mm pipe at the back of my meter
to the boiler but it could be run outside (around a 3m run) so long as
the pipe was held off the wall.

And properly sleeved etc. etc. All true.


d) To check the new system would cope/match my existing shower pump I
needed to lookup the output from my pump (i've struggles with this as
the plate on it quote 3 l/min numbers). Also, I needed to check the
spec of the shower valve in my ensuite to ensure it was OK for the new
increased standing pressure.


These are not the end of the world to replace later if they are
unsatisfactory.


e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height. (=2m).


That avoids the need for a terminal guard but no word on the possible
pluming problems and air-space wars.


f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.

Fair comment.


g) Mentioning some pipework in concrete floor he was unperturbed,
suggesting the increased pressure of my new sealed system was not that
high and if existing system was working I'd be OK.


See my previous post, however a positive attitude has much to commend it.

h) I mentioned past experience of combi boilers (over 12 years ago) and
he said the worcester 440 was miles ahead of whatever I had then and I
would not suffer from excessive reduced flow in winter. He did go on
quite a bit about what temperature my shower ran at and how I was mixing
alot of cold water with hot to get confortable.


Fair comment. This boiler has good performance at the expense of floor
space, size and weight.



i) he said my existing cylinder (although only 5 years old) was not up
to spec since it did not have 2" of insulation (I might have the exact
number wrong).


Possibly true.



j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.


The TRV must go. As discussed.


k) the worcester 440 had an in built 12l (I think) vessel which had some
advantage in the speed in which hot water reached my taps - not sure
exactly.


See 'f' and 'a' and 'h'


Cost 2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system) -
sealed system.

Probably about right.



o plumber number 2

quote not received yet but it was for a wall mounting Worcester 3XX
(something) 12l/min output at X degrees C rise (have not got the
brochure).

o concurred with plumber 1 than cylinder was not up to spec. Also said
the hot water feed to my shower pump was too high in the cylinder. Also
said the cylninder would be better turned through 90 degrees for easier
access to valve - fair enough.

o concurred with plumber 1 re TRV and room therm in same room.

o on business of 22mm gas feed to boiler - some needed it some don't -
often plumbers size up from 15 to 22 - a bit wishy washy - I was not
certain what was required but if a 22mm pipe was required as with
plumber 1 it could be run along outside wall.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.

o as with plumber 1 he'd need specs for ensuite shower valve as it might
not be up to increased standing pressure if we went combi boiler but the
myra shower valve in bathroom was certainly OK (I knew this anyway as
some tosser who previously installed shower in bathromm before we moved
here plumbed it in to the bath supply where the cold water was mains
pressure). When it leaked badly I needed to replace it in a hurry and
found I needed a more expensive valve to handle the imbalance. Since
then it has been replumbed to the cold tank.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did not
use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.

o servicing required for worcester 3XX was once every 12 to 18 months
and would cost around 50.

o room thermostat was required and they would not need to put cables in
as it was a (cableless) radio one.

o would quote for a powerflush at 395 which would take the best part
of a day as it involved connecting to heating system and flushing
through plus connecting to each radiator individually. When I suggested
this sounded alot (BG quoted 200) he said if the system had been
drained recently and was clean I could just ignore that in the quote.
They would have to drain the system twice anyway and lfush it with some
agent. He didn't try to sell it to me especially when I said the system
had been drained more than 5 times in the last 2 years alone and drained
out clean (also all of my radiators except one is brand new).

Someone who having got a powerflush gadget actually wishes to used only
when needed, a rare event, a mark of honesty perhaps?

o mains pressure was good in my area and not a worry.

o it cost them 5 to register the installation with Corgi who would
send me something I needed to keep as it would be required when I sold
my house.


Actually 4 by phone and 2.50 online. Hardly worth itemising really.
As to whether you _really_ will need it when you sell - who knows.
It is a legal requirement to register the exchange of a heating appliance
with building control it is done with this.


o gas mains was being updated in my area since it fell off too much (and
caused some boilers to shut down) early in the morning when all these
new condensing boilers switched on.


Some condensors are quite sensitive to under-pressure others are very
tolerant. Condensors use no more gas and possibly less than
non-condensors. Combis tend to place bigger peak
demands on the supply network. However if the mains are being fixed in
your area what's the problem?


What I think is a summary of the "true" bits of advice/information I
received from BG, local plumbers and this news group a

o you have to fit a condensing boiller unless you can amass 1000 pts on
a rather difficult to achieve scale. Certainly, a replacement boiler is
unlikey to achieve 1000 pts.

Yep


o plumning - I'm not going there - it seems a contentious issue.



o when moving to a condensing boiler you need a fully pumped system (no
gravity fed hot water) - this is law.

Yep

o don't have TRV on the radiator in the same room as a room thermostat -
also avoid rooms with other heat sources - kitchen, rooms with fires etc
Ed.

Just to be clear . TRVs are needed nearly everywhere. The roomstat is
needed somewhere but not with the TRV - in the hall is a good place.
remove existing TRV if needed.



o condensing boilers produce condensate which is slightly acidic and has
to have somewhere to drain away.

Yep


o some boilers come with bypass valves, some don't. You can't go all
TRVs without a bypass valve.


If the boiler says it needs a bypass you must have one TRVs or not.


o You need a "boiler interlock" that completely turns off the boiler
when the house is hot. Normally this is supplied by the room thermostat.
If there is none, another method must be used, such as a flow switch on
the heating circuit - thanks Christian/Andy/John.

Yep, but go for the room stat. The alternative gear will not be cheaper,
people will be less familiar with it. A programmble room stat can provided
an accessible heating control.

o some condensing boilers are modulating so instead of a constant power
output they adjust to conditions. Minimum outout of boiler is worht
looking at.

I don't think you'll find any fixed power modern boilers condensing or not.
The lower minimum the better. Provided the HW heating is OK (combi).
If you co for a cylinder then I suggest calculating the heating
requirements and then selecting the right sized boiler again lloking at
the minimum.

o There should be electrical bonding from the meter to the main earthing
point in the house. The service bonding ought to be done on the consumer
side of the meter rather than the supply as used to be the case.

Yep


o water cylinders are subject to building regs and upgrading a system
might (or must) mean upgrading the cylinder to current regs. Also, see
fast recovery cylinders (this was not mentioned to me by anyone
quoting).

A compliant cylinder is a fast(ish) cylinder.


Both plumbers seem to be saying the right sort of things give or take a
few details. The second one wishes to fit a cheaper lighter simpler combi
with much less HW output. Still good for shower (but probably not as good
as what you have with a pump).

If the wiring from the hall to the boiler is awkward then the 50 extra
for a wireless room stat could be worth the extra.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html


  #24   Report Post  
Mark
 
Posts: n/a
Default

On Tue, 21 Jun 2005 21:14:29 GMT, Martin Evans
wrote:

o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.


I have one of these. You only get the 20l/min for a short time, until
the internal thermal store is depleted. After that you get about 11/12
l/min (my estimate). I find it half fills a large bath before
dropping to the lower rate (you have to turn the taps down otherwise
you get cool water).

e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height.


I don't know what the fuss is all about pluming. It's only water
vapour and is rapidly dispersed.

f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.


Really? I don't remember mine reporting anything when I had a leak.
All I noticed was air in the system and the pressure dropping.

h) I mentioned past experience of combi boilers (over 12 years ago)
and he said the worcester 440 was miles ahead of whatever I had then
and I would not suffer from excessive reduced flow in winter. He did
go on quite a bit about what temperature my shower ran at and how I
was mixing alot of cold water with hot to get confortable.


In general combis are good for showers and not so good for baths.
YMMV.

j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.


Just get rid of the TRV on that radiator.

k) the worcester 440 had an in built 12l (I think) vessel which had
some advantage in the speed in which hot water reached my taps - not
sure exactly.


It has a thermal store internally (that's why it's so big).

Cost 2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system)
- sealed system.


Seems a good price. The boiler itself is very expensive.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.


Maybe you could rip out the old stuff yourself to save some cash.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did
not use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.


I doubt that an ordinary combi would be very good at supplying two
showers at the same time.

o mains pressure was good in my area and not a worry.


Also check your mains flow rate to make sure that is OK. (16l/min).

o condensing boilers produce condensate which is slightly acidic and
has to have somewhere to drain away.


Can go in a dedicated soakaway.

Mark

  #25   Report Post  
Doctor Evil
 
Posts: n/a
Default


"Mark" wrote in message
...
On Tue, 21 Jun 2005 21:14:29 GMT, Martin Evans
wrote:

o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.


I have one of these. You only get the 20l/min for a short time, until
the internal thermal store is depleted. After that you get about 11/12
l/min (my estimate). I find it half fills a large bath before
dropping to the lower rate (you have to turn the taps down otherwise
you get cool water).


The Alpha CD50 automatically reduces the water flow, when its substantial
store is depleted. The 440 HighFlow will fill an average bath, It still
will fill a large bath quick enough as it never runs out of hot water,
filling it in with tow stages of flow rate. Also the recovery rate is very
quick; a few minutes.

e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height.


I don't know what the fuss is all about pluming. It's only water
vapour and is rapidly dispersed.


It can make a wall very wet if directed against the wall, or the prevailing
wind blows it onto the wall.

f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.


Really? I don't remember mine reporting anything when I had a leak.
All I noticed was air in the system and the pressure dropping.


The newer models may do. The Greenstar 440 is a very new update.

h) I mentioned past experience of combi boilers (over 12 years ago)
and he said the worcester 440 was miles ahead of whatever I had then
and I would not suffer from excessive reduced flow in winter. He did
go on quite a bit about what temperature my shower ran at and how I
was mixing alot of cold water with hot to get confortable.


In general combis are good for showers and not so good for baths.
YMMV.


DON'T GENERALISE. The 440 is a very good combi and will fill an average
bath quickly. The Japanese Rinnai multi-points will fill as fast as any
unvented cylinder system, belting out the hot water.

j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.


Just get rid of the TRV on that radiator.

k) the worcester 440 had an in built 12l (I think) vessel which had
some advantage in the speed in which hot water reached my taps - not
sure exactly.


It has a thermal store internally (that's why it's so big).


About 60 to 70 litres.

Cost 2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system)
- sealed system.


Seems a good price. The boiler itself is very expensive.


He has to fit the condensing version. This can be fitted anywhere and has an
integral condensate pump, so there is no excuse not to fit the condensing
version. If he doesn't fit the condensing version he is breaking the law.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.


Maybe you could rip out the old stuff yourself to save some cash.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did
not use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.


I doubt that an ordinary combi would be very good at supplying two
showers at the same time.

o mains pressure was good in my area and not a worry.


Also check your mains flow rate to make sure that is OK. (16l/min).

o condensing boilers produce condensate which is slightly acidic and
has to have somewhere to drain away.


Can go in a dedicated soakaway.


The 440 has an integrated condensate pump to pump it into a drain that can
be way away.

The Greenstar condensing 440 Highflow is a good boiler and you will not be
disappointed with it.




  #26   Report Post  
Doctor Evil
 
Posts: n/a
Default


"Ed Sirett" wrote in message
news
On Tue, 21 Jun 2005 21:14:29 +0000, Martin Evans wrote:



o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

I Maybe wrong but IIRC all Greenstar boilers are condensing.


You are righht.

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.


Initially before the store of HW in the boiler gives out this is likely
true. The usability of the system is likely to be good enough except for
high speed bath running.


It will fill an average bath quite quickly. It is designed to do so.

b) it would be cheaper to install than keeping my existing system as
it was far less components and mostly required ripping (bypassing)
existing system out rather than renewing/replacing. Basically, the
cold water tank would be bypassed, the cylinder goes, my shower pump
goes, electrics are trivial since all that is needed it something to
the boiler. I liked the sound of losing my shower pump IF the output
at the shower head was as good since the shower pump is noisy.


A wall stat (preferrably programmable) will also be needed to comply with
current regs.


c) my gas supply to boiler was 15mm and needed to be 22mm. There is no
easy way to get a 22mm pipe from the 22mm pipe at the back of my meter
to the boiler but it could be run outside (around a 3m run) so long as
the pipe was held off the wall.


And properly sleeved etc. etc. All true.


d) To check the new system would cope/match my existing shower pump I
needed to lookup the output from my pump (i've struggles with this as
the plate on it quote 3 l/min numbers). Also, I needed to check the
spec of the shower valve in my ensuite to ensure it was OK for the new
increased standing pressure.


These are not the end of the world to replace later if they are
unsatisfactory.


e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height. (=2m).


That avoids the need for a terminal guard but no word on the possible
pluming problems and air-space wars.


f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.


Fair comment.

g) Mentioning some pipework in concrete floor he was unperturbed,
suggesting the increased pressure of my new sealed system was not that
high and if existing system was working I'd be OK.


See my previous post, however a positive attitude has much to commend it.

h) I mentioned past experience of combi boilers (over 12 years ago) and
he said the worcester 440 was miles ahead of whatever I had then and I
would not suffer from excessive reduced flow in winter. He did go on
quite a bit about what temperature my shower ran at and how I was mixing
alot of cold water with hot to get confortable.


Fair comment. This boiler has good performance at the expense of floor
space, size and weight.


And liberates an airing cupboard.

i) he said my existing cylinder (although only 5 years old) was not up
to spec since it did not have 2" of insulation (I might have the exact
number wrong).


Possibly true.


j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.


The TRV must go. As discussed.


k) the worcester 440 had an in built 12l (I think) vessel which had some
advantage in the speed in which hot water reached my taps - not sure
exactly.


See 'f' and 'a' and 'h'


Cost 2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system) -
sealed system.

Probably about right.


o plumber number 2

quote not received yet but it was for a wall mounting Worcester 3XX
(something) 12l/min output at X degrees C rise (have not got the
brochure).

o concurred with plumber 1 than cylinder was not up to spec. Also said
the hot water feed to my shower pump was too high in the cylinder. Also
said the cylninder would be better turned through 90 degrees for easier
access to valve - fair enough.

o concurred with plumber 1 re TRV and room therm in same room.

o on business of 22mm gas feed to boiler - some needed it some don't -
often plumbers size up from 15 to 22 - a bit wishy washy - I was not
certain what was required but if a 22mm pipe was required as with
plumber 1 it could be run along outside wall.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.

o as with plumber 1 he'd need specs for ensuite shower valve as it might
not be up to increased standing pressure if we went combi boiler but the
myra shower valve in bathroom was certainly OK (I knew this anyway as
some tosser who previously installed shower in bathromm before we moved
here plumbed it in to the bath supply where the cold water was mains
pressure). When it leaked badly I needed to replace it in a hurry and
found I needed a more expensive valve to handle the imbalance. Since
then it has been replumbed to the cold tank.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did not
use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.

o servicing required for worcester 3XX was once every 12 to 18 months
and would cost around 50.

o room thermostat was required and they would not need to put cables in
as it was a (cableless) radio one.

o would quote for a powerflush at 395 which would take the best part
of a day as it involved connecting to heating system and flushing
through plus connecting to each radiator individually. When I suggested
this sounded alot (BG quoted 200) he said if the system had been
drained recently and was clean I could just ignore that in the quote.
They would have to drain the system twice anyway and lfush it with some
agent. He didn't try to sell it to me especially when I said the system
had been drained more than 5 times in the last 2 years alone and drained
out clean (also all of my radiators except one is brand new).

Someone who having got a powerflush gadget actually wishes to used only
when needed, a rare event, a mark of honesty perhaps?

o mains pressure was good in my area and not a worry.

o it cost them 5 to register the installation with Corgi who would
send me something I needed to keep as it would be required when I sold
my house.


Actually 4 by phone and 2.50 online. Hardly worth itemising really.
As to whether you _really_ will need it when you sell - who knows.
It is a legal requirement to register the exchange of a heating appliance
with building control it is done with this.


o gas mains was being updated in my area since it fell off too much (and
caused some boilers to shut down) early in the morning when all these
new condensing boilers switched on.


Some condensors are quite sensitive to under-pressure others are very
tolerant. Condensors use no more gas and possibly less than
non-condensors.


They use a lot less gas than non-condensers, that is why the government has
legislated in favour of them.

Combis tend to place bigger peak
demands on the supply network. However if the mains are being fixed in
your area what's the problem?


What I think is a summary of the "true" bits of advice/information I
received from BG, local plumbers and this news group a

o you have to fit a condensing boiller unless you can amass 1000 pts on
a rather difficult to achieve scale. Certainly, a replacement boiler is
unlikey to achieve 1000 pts.


Yep


o plumning - I'm not going there - it seems a contentious issue.


o when moving to a condensing boiler you need a fully pumped system (no
gravity fed hot water) - this is law.

Yep

o don't have TRV on the radiator in the same room as a room thermostat -
also avoid rooms with other heat sources - kitchen, rooms with fires etc
Ed.


Just to be clear . TRVs are needed nearly everywhere. The roomstat is
needed somewhere but not with the TRV - in the hall is a good place.
remove existing TRV if needed.


o condensing boilers produce condensate which is slightly acidic and has
to have somewhere to drain away.


Yep

o some boilers come with bypass valves, some don't. You can't go all
TRVs without a bypass valve.


If the boiler says it needs a bypass you must have one TRVs or not.


o You need a "boiler interlock" that completely turns off the boiler
when the house is hot. Normally this is supplied by the room thermostat.
If there is none, another method must be used, such as a flow switch on
the heating circuit - thanks Christian/Andy/John.


Yep, but go for the room stat. The alternative gear will not be cheaper,
people will be less familiar with it. A programmble room stat can provided
an accessible heating control.

o some condensing boilers are modulating so instead of a constant power
output they adjust to conditions. Minimum outout of boiler is worht
looking at.

I don't think you'll find any fixed power modern boilers condensing or

not.

There are a few around. They are superb for mating with thermal stores.

The lower minimum the better. Provided the HW heating is OK (combi).
If you co for a cylinder then I suggest calculating the heating
requirements and then selecting the right sized boiler again lloking at
the minimum.

o There should be electrical bonding from the meter to the main earthing
point in the house. The service bonding ought to be done on the consumer
side of the meter rather than the supply as used to be the case.

Yep


o water cylinders are subject to building regs and upgrading a system
might (or must) mean upgrading the cylinder to current regs. Also, see
fast recovery cylinders (this was not mentioned to me by anyone
quoting).


A compliant cylinder is a fast(ish) cylinder.


Part L is not fast, just faster than before.

Both plumbers seem to be saying the right sort of things give or take a
few details. The second one wishes to fit a cheaper lighter simpler combi
with much less HW output. Still good for shower (but probably not as good
as what you have with a pump).

If the wiring from the hall to the boiler is awkward then the 50 extra
for a wireless room stat could be worth the extra.



  #27   Report Post  
Dave Plowman (News)
 
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In article ,
Doctor Evil wrote:
The Alpha CD50 automatically reduces the water flow, when its
substantial store is depleted. The 440 HighFlow will fill an average
bath, It still will fill a large bath quick enough as it never runs out
of hot water, filling it in with tow stages of flow rate. Also the
recovery rate is very quick; a few minutes.


Please explain why a small storage tank built in to a boiler which makes
it larger than necessary is preferable to a large storage tank which can
be situated near anywhere and overcomes the problems of that small one and
varying flow rates while filling a bath is such a good idea?

Unless, of course, it's all those leaking joints you manage when
attempting plumbing?

--
*Drugs may lead to nowhere, but at least it's the scenic route *

Dave Plowman London SW
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  #28   Report Post  
Dave Plowman (News)
 
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In article ,
Doctor Evil wrote:
Fair comment. This boiler has good performance at the expense of floor
space, size and weight.


And liberates an airing cupboard.


Is that to make room for the second combi? Or perhaps you've never had an
airing cupboard?

--
*I'm not a complete idiot, some parts are missing *

Dave Plowman London SW
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  #29   Report Post  
Doctor Evil
 
Posts: n/a
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"Dave Plowman (News)" wrote in message
...
In article ,
Doctor Evil wrote:
The Alpha CD50 automatically reduces the water flow, when its
substantial store is depleted. The 440 HighFlow will fill an average
bath, It still will fill a large bath quick enough as it never runs out
of hot water, filling it in with tow stages of flow rate. Also the
recovery rate is very quick; a few minutes.


Please explain why a small
storage tank built in to a boiler
which makes it larger than
necessary is preferable to a
large storage tank which can
be situated near anywhere


You have been told many time, it is clear you lack basic comprehension. And
put those DO NOT USE labels back on your gas appliances - the one you took
off.

  #30   Report Post  
Doctor Evil
 
Posts: n/a
Default


"Dave Plowman (News)" wrote in message
...
In article ,
Doctor Evil wrote:


Fair comment. This boiler has good performance at the expense of floor
space, size and weight.


And liberates an airing cupboard.


Is that to make room for
the second combi?


I don't know, I don't live there. Do you live there? Can you tell us what
it is like inside?



  #31   Report Post  
Dave Plowman (News)
 
Posts: n/a
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In article ,
Doctor Evil wrote:
Please explain why a small
storage tank built in to a boiler
which makes it larger than
necessary is preferable to a
large storage tank which can
be situated near anywhere


You have been told many time, it is clear you lack basic comprehension.


Certainly by you. But then basic comprehension of any problem doesn't seem
to be your strong point given your 'one size fits all approach' But then
since you live on your own in a one bed flat I'm not surprised.

And put those DO NOT USE labels back on your gas appliances - the one
you took off.


So you approve of bent CORGI engineers? Even CORGI didn't when I reported
him.

--
*I can see your point, but I still think you're full of ****.

Dave Plowman London SW
To e-mail, change noise into sound.
  #32   Report Post  
John Rumm
 
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Doctor Evil wrote:

"Mark" wrote in message


l/min (my estimate). I find it half fills a large bath before
dropping to the lower rate (you have to turn the taps down otherwise
you get cool water).


The Alpha CD50 automatically reduces the water flow, when its substantial
store is depleted.


You still need to adjust the taps because the hot/cold mix will now be
wrong and you will end up with a cold mix.

BTW, we are not talking about a CD50 here....


--
Cheers,

John.

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  #33   Report Post  
Dave Plowman (News)
 
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In article ,
Doctor Evil wrote:
Fair comment. This boiler has good performance at the expense of
floor space, size and weight.


And liberates an airing cupboard.


Is that to make room for
the second combi?


I don't know, I don't live there. Do you live there? Can you tell us
what it is like inside?


So suddenly you're aware that not all houses or flats are the same as your
ex council one bedroom?

At last.

--
*Speak softly and carry a cellular phone *

Dave Plowman London SW
To e-mail, change noise into sound.
  #34   Report Post  
Andy Hall
 
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On Thu, 23 Jun 2005 11:26:03 +0100, "Doctor Evil"
wrote:



The Alpha CD50 automatically reduces the water flow, when its substantial
store is depleted.


The store is *not* substantial. It is 50-something litres.


The 440 HighFlow will fill an average bath,


Small bath.

It still
will fill a large bath quick enough as it never runs out of hot water,
filling it in with tow stages of flow rate.


The second being very slow.




DON'T GENERALISE.


That's rich coming from you



He has to fit the condensing version. This can be fitted anywhere and has an
integral condensate pump, so there is no excuse not to fit the condensing
version. If he doesn't fit the condensing version he is breaking the law.


That is not necessarily always true. There may be an exemption based
on the points system in some cases. While it is desirable to fit a
condensing boiler and in most cases insufficient points will be
achieved for exemption, it is a generalisation to say that a
condesning product must always be fitted.





--

..andy

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The information contained in this post is copyright the
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  #35   Report Post  
Ed Sirett
 
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On Thu, 23 Jun 2005 10:46:33 +0100, Mark wrote:


I don't know what the fuss is all about pluming. It's only water
vapour and is rapidly dispersed.

You know that, I know that, the OP knows that. Maybe his neighbour doesn't.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html




  #36   Report Post  
Doctor Evil
 
Posts: n/a
Default


"
"Dave Plowman (News)" wrote in message
...
In article ,
Doctor Evil wrote:
Please explain why a small
storage tank built in to a boiler
which makes it larger than
necessary is preferable to a
large storage tank which can
be situated near anywhere


You have been told many time, it is clear you lack basic comprehension.


Certainly by you.


Yes, by me. I have told you many times.


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  #37   Report Post  
Doctor Evil
 
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"John Rumm" wrote in message
...
Doctor Evil wrote:

"Mark" wrote in message


l/min (my estimate). I find it half fills a large bath before
dropping to the lower rate (you have to turn the taps down otherwise
you get cool water).


The Alpha CD50 automatically reduces the water flow, when its

substantial
store is depleted.


You still need to adjust the taps because the hot/cold mix will now be
wrong and you will end up with a cold mix.

BTW, we are not talking about a CD50 here....


I know. But a CD50 does it automatically. You see this adds value to the
conversation. They obviously don't do this Essex. The new 440 may do, I
haven't looked.


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  #38   Report Post  
Doctor Evil
 
Posts: n/a
Default


"Dave Plowman (News)" wrote in message
...
In article ,
Doctor Evil wrote:
Fair comment. This boiler has good performance at the expense of
floor space, size and weight.

And liberates an airing cupboard.

Is that to make room for
the second combi?


I don't know, I don't live there. Do you live there? Can you tell us
what it is like inside?


So suddenly you're aware that not all houses or flats are the same as your
ex council one bedroom?


How is the sink estate today? Hot and bothered. Maybe a riot tonight, if
you are lucky.


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  #39   Report Post  
Doctor Evil
 
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"Andy Hall" wrote in message
...
On Thu, 23 Jun 2005 11:26:03 +0100, "Doctor Evil"
wrote:



The Alpha CD50 automatically reduces the water flow, when its substantial
store is depleted.


The store is *not* substantial. It is 50-something litres.


About 60. It fills an average bath pronto.

The 440 HighFlow will fill an average bath,


Small bath.


Average bath. You have never seen one, so don't even comment on it.

It still will fill a large bath quick enough
as it never runs out of hot water,
filling it in with tow stages of flow rate.


The second being very slow.


Overall fill speed quick.

DON'T GENERALISE.


That's rich coming from you


I am avery rich person.

He has to fit the condensing version.
This can be fitted anywhere and has an
integral condensate pump, so there is
no excuse not to fit the condensing
version. If he doesn't fit the condensing
version he is breaking the law.


That is not necessarily always true.
There may be an exemption based
on the points system in some cases.


Highly unlikely as the boiler a highly flexible fluing and condensate
system.


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  #40   Report Post  
John Rumm
 
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Doctor Evil wrote:

You still need to adjust the taps because the hot/cold mix will now be
wrong and you will end up with a cold mix.

BTW, we are not talking about a CD50 here....



I know. But a CD50 does it automatically.


So you are saying that it will adjust the bath taps for you now?

You really are an ad man's wet dream.


--
Cheers,

John.

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