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John Powell
 
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Default Combi-Boiler Choice- ?Alpha any good

I've finally got the builders in - need to make final choice re
combi-boiler.

House is medium-large semi, present back-boiler system going in the
bin

I want a high flow system so I can have a decent shower

- the builder's recommended a "Alpha CB50"

http://www.alpha-boilers.com/products/CB50.html

This provides a high flow rate - 18l/min @ 60 degrees C until the
internal 60l cylinder is exhausted, then a flow rate of 9-10 l/min @
45 degrees indefinitely

Is this an ideal system for a good shower? I'm concerned that my
showers are going to be short ones at a decent flow rate.

Would I be better going for a combi-boiler without an internal storage
cylinder, but a high flow rate anyway, perhaps the Baxi Combi 130HE?

any advice would be appreciated

John
  #2   Report Post  
Christian McArdle
 
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Default Combi-Boiler Choice- ?Alpha any good

I want a high flow system so I can have a decent shower

- the builder's recommended a "Alpha CB50"


I know nothing about alpha as a company or their products. However, the
specification of the hot water side looks good and should be enough for your
needs, unless you are planning a panel shower or other such monstrosity. It
isn't condensing, though, so has 80% efficiency, rather than 90% efficiency.
That will add over 10% to your fuel bills compared with a condensing type
(but will save at least as much compared to your old back boiler).

Christian,


  #3   Report Post  
John Rumm
 
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Default Combi-Boiler Choice- ?Alpha any good

John Powell wrote:

I want a high flow system so I can have a decent shower


For an "ordinary" shower then this boiler would be more than adequate.
In fact anything that can do 10L/min or better will be more than you
need for a single shower usually.

- the builder's recommended a "Alpha CB50"

http://www.alpha-boilers.com/products/CB50.html

This provides a high flow rate - 18l/min @ 60 degrees C until the
internal 60l cylinder is exhausted, then a flow rate of 9-10 l/min @
45 degrees indefinitely

Is this an ideal system for a good shower? I'm concerned that my
showers are going to be short ones at a decent flow rate.


They make it quite tricky to find any technical specs on the web site -
but you can download the installation manual which has most of the info
you need. The boiler itself has a direct hot water heat input rating of
33kW - which is toward the larger end, but not the biggest you can buy.
Efficency at 80% is poor (and reduces the real DHW heating capacity to a
real world 26.4kW once its tank is cold). So most of the impressive DHW
performance comes from the 57L tank that is built in.

The main benefit of a storage system like this will tend to be better
performance when filling baths.

Would I be better going for a combi-boiler without an internal storage
cylinder, but a high flow rate anyway, perhaps the Baxi Combi 130HE?


I have no idea what Alpha are like, so will not give any recomendation.
If you want to shop around then I would have thought that it might be
worth looking at condencing combis with a heat input of 30kW or better.
There are a number to choose from.

Price looks OK at just over the grand:-

http://inspiredheating.co.uk/acatalo...D_COMBI_S.html


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #4   Report Post  
IMM
 
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Default Combi-Boiler Choice- ?Alpha any good


"John Rumm" wrote in message
...
John Powell wrote:

I want a high flow system so I can have a decent shower


For an "ordinary" shower then this boiler would be more than adequate.
In fact anything that can do 10L/min or better will be more than you
need for a single shower usually.

- the builder's recommended a "Alpha CB50"

http://www.alpha-boilers.com/products/CB50.html

This provides a high flow rate - 18l/min @ 60 degrees C until the
internal 60l cylinder is exhausted, then a flow rate of 9-10 l/min @
45 degrees indefinitely

Is this an ideal system for a good shower? I'm concerned that my
showers are going to be short ones at a decent flow rate.


They make it quite tricky to find any technical specs on the web site -
but you can download the installation manual which has most of the info
you need. The boiler itself has a direct hot water heat input rating of
33kW - which is toward the larger end, but not the biggest you can buy.
Efficency at 80% is poor (and reduces the real DHW heating capacity to a
real world 26.4kW once its tank is cold). So most of the impressive DHW
performance comes from the 57L tank that is built in.

The main benefit of a storage system like this will tend to be better
performance when filling baths.

Would I be better going for a combi-boiler without an internal storage
cylinder, but a high flow rate anyway, perhaps the Baxi Combi 130HE?


I have no idea what Alpha are like, so will not give any recomendation.
If you want to shop around then I would have thought that it might be
worth looking at condencing combis with a heat input of 30kW or better.
There are a number to choose from.

Price looks OK at just over the grand:-

http://inspiredheating.co.uk/acatalo...D_COMBI_S.html


Just over 1K? Then here is what I suggested in another thread:
Good simple combi's are Ferroli Modena and Worcester Bosch Junior at around
11 to 12 litres/min. Great for frequent showers and a simple designs with
no 3-ways valves.

For high flowrates it is cost effective to use two Juniors and combine the
outlets. Worcester will supply a drawing on how to do it. Two Juniors are
available for around £1000 to 1100 depending on what sized units you buy.
They have 24 and 28 kW you could use two 24kW or two 28 kW combi's or one of
each. That is cheaper than the Worcester HighFlow 18 litres/min floor
mounted combi and can deliver about 21.5 litres/min and never run out
of hot water.

Have one combi do the downstairs heating on its own programmer/timer and one
do upstairs. Natural zoning, so you don't have to heat upstairs when you
are not up there saving fuel. The running cost will approx the same as a
condensing boiler heating the whole house. No external zone valves either,
and simple wiring up too. Also if one goes down you will have another combi
to give some heat in the house and DHW too. Combine the outlets for DHW and
all the baths you want very quickly and no waiting. It will do two showers
no problem at all. A win, win, situation.



  #5   Report Post  
John Powell
 
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Default Combi-Boiler Choice- ?Alpha any good

John Rumm wrote in message .. .
John Powell wrote:

I want a high flow system so I can have a decent shower


For an "ordinary" shower then this boiler would be more than adequate.

snip

One potential problem for me is the apparent low flow rate into the
house from the mains

I did a check at the nearest cold tap to the water inlet, ( the cold
water is at mains pressure) - I filled a 2 litre jug and timed it

it came out at about 15l/min

would that change the optimum choice of boiler?

thanks

John


  #6   Report Post  
IMM
 
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Default Combi-Boiler Choice- ?Alpha any good


"John Powell" wrote in message
om...
John Rumm wrote in message

.. .
John Powell wrote:

I want a high flow system so I can have a decent shower


For an "ordinary" shower then this
boiler would be more than adequate.
snip


One potential problem for me is the
apparent low flow rate into the
house from the mains

I did a check at the nearest cold tap
to the water inlet, ( the cold
water is at mains pressure) - I filled a
2 litre jug and timed it

it came out at about 15l/min

would that change the optimum choice of boiler?


Yes. No more than 15 litres/min. This will still give you a decent high
pressure shower. Is the stop cock fully open? Is the cock in the street
fully open? Do the neighbours have similar flowrates? If you mainly have
showers and can wait a few more minutes to fill a bath on the odd occasions
you have one, then all is fine. It may be worth looking into replacing the
mains pipe to larger 25mm bore back to the road. This is well worth
considering. Once done it is fine for ever. If you want fast bath fills
frequently and you don't want to upgrade your mains pipe, then you will have
to go tank/cylinder

If you go tank cylinder then use a Fortic type of tank/cylinder combination
unit (this is all one insulated unit and can go in the loft) with an
integral quick recovery coil. Have a combi (Worcester Junior is having good
reports of late; and simple) heat the cylinder as per usual, but with a
priority system of DHW. have the shower only through the water section of
the combi giving high pressure showers and all other hot outlets from the
tank/cylinder. You only did high pressure at the shower, all the rest need
volume not pressure.



  #7   Report Post  
 
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Default Combi-Boiler Choice- ?Alpha any good

On Wed, 31 Mar 2004 09:13:56 +0100, "IMM" wrote:

If you go tank cylinder then use a Fortic type of tank/cylinder combination
unit (this is all one insulated unit and can go in the loft) with an
integral quick recovery coil. Have a combi (Worcester Junior is having good
reports of late; and simple) heat the cylinder as per usual, but with a
priority system of DHW. have the shower only through the water section of
the combi giving high pressure showers and all other hot outlets from the
tank/cylinder. You only did high pressure at the shower, all the rest need
volume not pressure.


How do you get a combi boiler to heat a cylinder?



  #8   Report Post  
 
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Default Combi-Boiler Choice- ?Alpha any good

On Tue, 30 Mar 2004 17:48:07 +0100, "Christian McArdle"
wrote:

I want a high flow system so I can have a decent shower

- the builder's recommended a "Alpha CB50"


I know nothing about alpha as a company or their products. However, the
specification of the hot water side looks good and should be enough for your
needs, unless you are planning a panel shower or other such monstrosity. It
isn't condensing, though, so has 80% efficiency, rather than 90% efficiency.
That will add over 10% to your fuel bills compared with a condensing type
(but will save at least as much compared to your old back boiler).


But aren't condensing boilers a lot more expensive to buy?

For example:
Vokera Compact 28 £515
Vokera Syntesi 29 £720

It would take a while for it to pay back the difference.

M

  #9   Report Post  
Adrian Ball
 
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Default Combi-Boiler Choice- ?Alpha any good

(John Powell) wrote in message . com...

[SNIP]
Would I be better going for a combi-boiler without an internal storage
cylinder, but a high flow rate anyway, perhaps the Baxi Combi 130HE?


We have a Baxi 130HE. Great boiler technically, shame the same cannot
be said about their service engineers (or customer service for that
matter!).
I would not recommend buying a Baxi product purely for this reason.

Our boiler had a simple fault, the valve which is supposed to stop
flow to the central heating when hot water is drawn never operated.
None of the engineers (including a 'senior' one) believed there was a
fault, coming up with all sorts of vague "reasons" for the poor
performance. One engineer replaced the control board (thinking, with
no evidence, that this would cure the problem), then failed to believe
that it had to be set up to use the intellistat - he actually insisted
(without checking) that it didn't need setting up, and left. Two
hours later, we had a cold house and I had to dig out the manual and
do it myself. This is on top of two week waiting lists for service
appointments, and one missed appointment (with no notification).
Eventually (after six months of high gas bills and poor hot water),
the fault became clear as the warmer weather started and we had a red
hot house everytime someone had a shower - they replaced the valve
(after we had presented them with clear evidence of the fault, no
investigation on their part) - no problems since...

Customer service never responded to our letter of complaint (or our
installer's independent letter).

Good boiler - bad service - don't go there!
  #10   Report Post  
John Rumm
 
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Default Combi-Boiler Choice- ?Alpha any good

IMM wrote:

to give some heat in the house and DHW too. Combine the outlets for DHW and
all the baths you want very quickly and no waiting. It will do two showers
no problem at all. A win, win, situation.


While there are attractions to a two combi system, to describe it as a
win win situation would be a best misleading.

One factor you always seem to ignore when presenting this argument is
the cost of installation. While the cost of the boilers may not work out
costing much more than the cost of a larger boiler, it is going to cost
getting on for double the amount to install. In many cases the cost of
installing is significantly more than the cost of the boiler.

If you go for two boilers on different floors, then you also need to
find a place to install the second - in many properties this is not a
trivial task. You are going to be paying to have two boilers serviced
annualy as well.

There are advantages and also disadvantages of any setup - a win / loose
situation.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/


  #11   Report Post  
John Rumm
 
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Default Combi-Boiler Choice- ?Alpha any good

John Powell wrote:

One potential problem for me is the apparent low flow rate into the
house from the mains

I did a check at the nearest cold tap to the water inlet, ( the cold
water is at mains pressure) - I filled a 2 litre jug and timed it

it came out at about 15l/min

would that change the optimum choice of boiler?


I had this concern myself since we have a poor (ish) mains feed. I found
I actually got the best flow rate at the cold bath tap however (the
kitchen tap is a monobloc mixer with microbore feed, and was giving a
misleading impression that the feed was capable of 5 or more l/min less
than was actually the case). So it might be worth repeating the test at
another tap if possible. Use a larger container and time say 10 litres
to get a more accurate picture.

If the limit really is 15 l/min then you have three choices:-

1) live with it, since it is plenty good enough for a shower, and is not
going to restrict the performance of any combi below 38kW (i.e. quite large)

2) Upgrade the mains feed

3) Fit a mains pressure unvented cylinder, and heat it like you would a
conventional hot water cylinder.

Option 2 is worth doing if you are looking for a very high end combi
system (or multiple combis).

Option 3 will outperform the combi systems for things like bath filling
but cost as much or more than IMM's "a boiler for every room of the
house" scheme.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #12   Report Post  
IMM
 
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Default Combi-Boiler Choice- ?Alpha any good


"John Rumm" wrote in message
...
IMM wrote:

to give some heat in the house and DHW too.
Combine the outlets for DHW and
all the baths you want very quickly and no
waiting. It will do two showers
no problem at all. A win, win, situation.


While there are attractions to a two
combi system, to describe it as a
win win situation would be a best misleading.

One factor you always seem to ignore
when presenting this argument is
the cost of installation.


That is the point, it is cheap to install, with no zone valves, etc.

While the cost of the boilers may not work out
costing much more than the cost of a larger boiler,
it is going to cost getting on for double the
amount to install.


Absolute nonsense. If anything it will be CHEAPER to install. In an
existing system, separating the system to upstairs and down may in some case
prove problematic, but in most system the upstairs and downstairs are two
separate loops.

This is a TWO zone setup. If you wanted the same from a single boiler it
would be more complicated and the same applies to the pipework runs pof
both.

In many cases the cost of
installing is significantly more than
the cost of the boiler.


Absolute nonsense !!!!!

If you go for two boilers on
different floors, then you also need to
find a place to install the second - in
many properties this is not a
trivial task.


You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant cylinder.

You are going to be paying to have
two boilers serviced
annualy as well.


You can always get a deal with two boiers when they next to each other.

There are advantages and also disadvantages
of any setup - a win / loose situation.


The two combi setup, has few disadvantages and the only one you picked up on
is the increased cost of servicing, which is not a great amount. The Junior
doesn't even have a 3-way valve making it more reliable. Every other point
you raised was wrong. Two Worcester-Bosch Juniors cost from under £100 to
around £1100. Giving approx 21.3 litres/minute. Go and find a single
boiler that can do that at that price. The ECO-Hometec, although a
condensing boiler, can go to 22 litres/min, but at just under 2K for it.
And when it is down no heat or hot water, unike the two combi setup.


  #13   Report Post  
IMM
 
Posts: n/a
Default Combi-Boiler Choice- ?Alpha any good


"John Rumm" wrote in message
...
John Powell wrote:

One potential problem for me is the apparent low flow rate into the
house from the mains

I did a check at the nearest cold tap to the water inlet, ( the cold
water is at mains pressure) - I filled a 2 litre jug and timed it

it came out at about 15l/min

would that change the optimum choice of boiler?


I had this concern myself since we have a poor (ish) mains feed. I found
I actually got the best flow rate at the cold bath tap however (the
kitchen tap is a monobloc mixer with microbore feed, and was giving a
misleading impression that the feed was capable of 5 or more l/min less
than was actually the case). So it might be worth repeating the test at
another tap if possible. Use a larger container and time say 10 litres
to get a more accurate picture.

If the limit really is 15 l/min then you have three choices:-

1) live with it, since it is plenty good enough for a shower, and is not
going to restrict the performance of any combi below 38kW (i.e. quite

large)

2) Upgrade the mains feed

3) Fit a mains pressure unvented cylinder, and heat it like you would a
conventional hot water cylinder.

Option 2 is worth doing if you are looking for a very high end combi
system (or multiple combis).

Option 3 will outperform the combi
systems for things like bath filling


Not so. The Alpha CB50 combi will perform just the same. In fact it has an
unvented cyoidner inside it, and will revert to a,ow flowrate when the
cyinder is empty, which should be very rare in anormal one bathroom house.

but cost as much or more than IMM's
"a boiler for every room of the
house" scheme.


Nothing like a know-it-all amateur is there.


  #14   Report Post  
Andy Hall
 
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Default Combi-Boiler Choice- ?Alpha any good

On Wed, 31 Mar 2004 17:09:40 +0100, "IMM" wrote:


"John Rumm" wrote in message
.. .
IMM wrote:


One factor you always seem to ignore
when presenting this argument is
the cost of installation.


That is the point, it is cheap to install, with no zone valves, etc.


Zone valves are hardly expensive, are they?


While the cost of the boilers may not work out
costing much more than the cost of a larger boiler,
it is going to cost getting on for double the
amount to install.


Absolute nonsense. If anything it will be CHEAPER to install. In an
existing system, separating the system to upstairs and down may in some case
prove problematic, but in most system the upstairs and downstairs are two
separate loops.


Really? This rather depends on whether the pipes run under the
ground floor, doesn't it?



This is a TWO zone setup. If you wanted the same from a single boiler it
would be more complicated and the same applies to the pipework runs pof
both.

In many cases the cost of
installing is significantly more than
the cost of the boiler.


Absolute nonsense !!!!!


Labour costs in what has become a premium trade are not cheap......




If you go for two boilers on
different floors, then you also need to
find a place to install the second - in
many properties this is not a
trivial task.


You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant cylinder.


.... needing a gas supply to be run there.....


You are going to be paying to have
two boilers serviced
annualy as well.


You can always get a deal with two boiers when they next to each other.


Hmmm......


There are advantages and also disadvantages
of any setup - a win / loose situation.


The two combi setup, has few disadvantages and the only one you picked up on
is the increased cost of servicing, which is not a great amount.


Only double, but that's not a lot, I suppose.

The Junior
doesn't even have a 3-way valve making it more reliable. Every other point
you raised was wrong. Two Worcester-Bosch Juniors cost from under £100 to
around £1100. Giving approx 21.3 litres/minute. Go and find a single
boiler that can do that at that price. The ECO-Hometec, although a
condensing boiler, can go to 22 litres/min, but at just under 2K for it.
And when it is down no heat or hot water, unike the two combi setup.


If any boiler is so bad that it needs a second unit as a backup in a
domestic situation, then it doesn't deserve house room.

An immersion heater in a cylinder is a more useful solution in the
event of boiler failure since a totally separate energy source is used
as well.


..andy

To email, substitute .nospam with .gl
  #15   Report Post  
IMM
 
Posts: n/a
Default Combi-Boiler Choice- ?Alpha any good


"Andy Hall" wrote in message
...
On Wed, 31 Mar 2004 17:09:40 +0100, "IMM" wrote:

"John Rumm" wrote in message
.. .
IMM wrote:


One factor you always seem to ignore
when presenting this argument is
the cost of installation.


That is the point, it is cheap to install, with no zone valves, etc.


Zone valves are hardly expensive, are they?


They are. You will need three with a normal boiler. Then there is the
fittings and pipe and pressure by-pass valve, etc. The Junior comes
complete with one inside.

While the cost of the boilers may not work out
costing much more than the cost of a larger boiler,
it is going to cost getting on for double the
amount to install.


Absolute nonsense. If anything it will be CHEAPER to install. In an
existing system, separating the system to upstairs and down may in some

case
prove problematic, but in most system the upstairs and downstairs are two
separate loops.


Really? This rather depends on whether the pipes run under the
ground floor, doesn't it?


Read on...

This is a TWO zone setup. If you wanted the same from a single boiler it
would be more complicated and the same applies to the pipework runs pof
both.

In many cases the cost of
installing is significantly more than
the cost of the boiler.


Absolute nonsense !!!!!


Labour costs in what has become a
premium trade are not cheap......


Read what I wrote above. It is clear.

If you go for two boilers on
different floors, then you also need to
find a place to install the second - in
many properties this is not a
trivial task.


You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant cylinder.


... needing a gas supply to be run there.....


Great thing eh!

You are going to be paying to have
two boilers serviced
annualy as well.


You can always get a deal with two boiers when they next to each other.


Hmmm......


There are advantages and also disadvantages
of any setup - a win / loose situation.


The two combi setup, has few disadvantages
and the only one you picked up on
is the increased cost of servicing, which is not
a great amount.


Only double, but that's not a lot, I suppose.


Nonsense again. No zone valves of any sort would be in the system, either
externally or in the combi's. This make the system as whole far more
reliable, with built-in redundancy.

The Junior
doesn't even have a 3-way valve making it more reliable. Every other

point
you raised was wrong. Two Worcester-Bosch Juniors cost from under £100 to
around £1100. Giving approx 21.3 litres/minute. Go and find a single
boiler that can do that at that price. The ECO-Hometec, although a
condensing boiler, can go to 22 litres/min, but at just under 2K for it.
And when it is down no heat or hot water, unike the two combi setup.


If any boiler is so bad that it needs a second unit as a backup in a
domestic situation, then it doesn't deserve house room.


You clear haven't a clue. Another know-it-all. Read what I wrote again.
Read about the system and its advantages in:

- space saving,
- redundancy,
- high flowrates,
- Natural zoning,
- hardly any electrical control work (running a wire to a programmers/stat
and power to each,
- simple no brainer installation,
- minimal components used.
- etc.

Now read it again and come back with sensible questions.

This method is catching on and most makers now, will give a diagram on how
to combine the outlets of the boilers. Worcester-Bosch will give one.

An immersion heater in a cylinder
is a more useful solution in the
event of boiler failure since a totally
separate energy source is used
as well.


You haven't read the thread have you?




  #16   Report Post  
Andy Hall
 
Posts: n/a
Default Combi-Boiler Choice- ?Alpha any good

On Wed, 31 Mar 2004 18:00:26 +0100, "IMM" wrote:




That is the point, it is cheap to install, with no zone valves, etc.


Zone valves are hardly expensive, are they?


They are.


In the context of a complete installation not at all.

You will need three with a normal boiler. Then there is the
fittings and pipe and pressure by-pass valve, etc. The Junior comes
complete with one inside.


Which will be reflected in the cost. It isn't "free".





Read what I wrote above. It is clear.


With your writings, clarity is not a description that I would use all
that much.




You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant cylinder.


... needing a gas supply to be run there.....


Great thing eh!


It all adds to the cost.



The two combi setup, has few disadvantages
and the only one you picked up on
is the increased cost of servicing, which is not
a great amount.


Only double, but that's not a lot, I suppose.


Nonsense again. No zone valves of any sort would be in the system, either
externally or in the combi's. This make the system as whole far more
reliable, with built-in redundancy.


What you are describing does not equate to redundancy. You are
talking about a boiler per zone for heating and hot water. Since
you have described these as being autonomous systems because of lack
of zone valves, it is not redundant in the least.

Redundancy would happen if both boilers were plumbed together in such
a way that one would take over from the other in the event of failure
or both run at part load with the ability to cover for the other in
the event of failure. This would require an altogether more complex
form of controls and components to implement.

Having HW and heating available in only part of the house is not
redundancy, it's impaired service - not the same thing at all..





You clear haven't a clue.


I clearly do

Another know-it-all.


If you look at your typical posting style, evident in this case, there
is only ever one way, as far as you are concerned and everything and
everybody else is wrong.

I grew out of that attitude before my tenth birthday,


Read what I wrote again.
Read about the system and its advantages in:

- space saving,


compared to what? Certainly not one boiler.

- redundancy,


Definitely not.

- high flowrates,


It depends on what you mean by high.

- Natural zoning,


which could more easily be achieved with zone valves.

- hardly any electrical control work (running a wire to a programmers/stat
and power to each,


Marginal difference to a zoned installation.


- simple no brainer installation,


at a cost in terms of implementation of services etc.

- minimal components used.
- etc.


I'm not sure what the etc. is. It's one thing having multiple
boilers in a commercial installation, correctly implemented; of little
benefit in a domestic one.


Now read it again and come back with sensible questions.


I don't have any questions.



This method is catching on and most makers now, will give a diagram on how
to combine the outlets of the boilers. Worcester-Bosch will give one.


I bet they will.




..andy

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  #17   Report Post  
IMM
 
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"Andy Hall" wrote in message
...
On Wed, 31 Mar 2004 18:00:26 +0100, "IMM" wrote:


That is the point, it is cheap to install,
with no zone valves, etc.

Zone valves are hardly expensive, are they?


They are.


In the context of a complete
installation not at all.

You will need three with a normal boiler.
Then there is the fittings and pipe and
pressure by-pass valve, etc. The Junior comes
complete with one inside.


Which will be reflected in the cost. It isn't "free".


I gave the cost of two.

Read what I wrote above. It is clear.


With your writings, clarity is not a description
that I would use all that much.


You don't read properly. I am very clear.

You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant

cylinder.

... needing a gas supply to be run there.....


Great thing eh!


It all adds to the cost.


Not much

The two combi setup, has few disadvantages
and the only one you picked up on
is the increased cost of servicing, which is not
a great amount.

Only double, but that's not a lot, I suppose.


Nonsense again. No zone valves of any
sort would be in the system, either
externally or in the combi's. This make the
system as whole far more
reliable, with built-in redundancy.


What you are describing does not
equate to redundancy. You are
talking about a boiler per zone for heating
and hot water. Since you have described
these as being autonomous systems because of lack
of zone valves, it is not redundant in the least.


You will have heat in the house if one fails.

Redundancy would happen if both
boilers were plumbed together in such
a way that one would take over from the
other in the event of failure


That can be dow by linking them up and having a full bore valve on the link.
One down turn it on by the valve and both are pumpoing into both rad
circuits. Cheap and simple.

Having HW and heating available in
only part of the house is not
redundancy, it's impaired service - not
the same thing at all..


Better than no heat at all. Simple to link them up. See above.

You clear haven't a clue.


I clearly do...not have a clue.


Another know-it-all.


If you look at your typical posting style,
evident in this case, there
is only ever one way, as far as you are
concerned and everything and
everybody else is wrong.


This solution is the one in question. You clearly cannot assess such a
system in cost, functionality and simplicity.

I grew out of that attitude before my tenth birthday,


You must still be under 10 then.

Read what I wrote again.
Read about the system and its advantages in:

- space saving,


compared to what? Certainly not one boiler.


snip garbage

You clearly haven't a clue and lack simple analytical skills. Which is sad.


  #18   Report Post  
John Rumm
 
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IMM wrote:

I think I am beginning to understand why my spell checker always wants
to change IMM to DIM....

That is the point, it is cheap to install, with no zone valves, etc.


OK I will take it nice and slowly for you, see if you can keep up (feel
free to move your lips as you read if it helps)

How do you work out the cost of installing a boiler?

Well there are two parts to the equation: parts and labour.

What parts do we need? Some copper pipe + fittings, solder, flux, and an
assortment of valves etc depending on the type of install we are doing.
Factor in a bit of wear on your core bore when drilling the flue, and
some gas for your blowtorch, petrol etc. and you have a couple of
hundred perhaps.

Now lets assume it is a pretty straight forward operation and one man
gets it done in a day. That will be 8 hours at anything from 70 quid
per hour upwards - so including the parts that would be 760 or more.

Of course in the OPs situation he was looking to replace a back boiler -
that is not going to be so quick and easy. Parts won't cost much more -
labour will.

What does your boiler cost? Comparable to the parts + labour charge I
would have thought. So my statement that the cost of installing the
boiler is going to cost about the same as the boiler is I would say fair.

Now lets say you want ot install two of them. Cost of parts will may be
similar maybe less or perhaps more if there is much new pipework to
install. Draining down only needs to be done once so you save a little
there. Pretty much everything else is going to take the same amount of
time again. Hence getting on for double the labour costs.

Absolute nonsense. If anything it will be CHEAPER to install. In an


Perhaps in the IMM time vortex one man can install two boilers in half
time time it takes the same man to install one...

Hmm yup see your logic there. How is K9 these days?

existing system, separating the system to upstairs and down may in some case
prove problematic, but in most system the upstairs and downstairs are two
separate loops.


As a generalisation that probably does not work.... most modern houses
with solid floors downstairs will be plumbed as one loop under the first
floor. Older properties with susspended floors may have two loops. Not
really relevant either way since we are talking about retrofitting a new
boiler to an existing heating system.

This is a TWO zone setup. If you wanted the same from a single boiler it
would be more complicated and the same applies to the pipework runs pof
both.


So you are saying: It would be more complicated for a single boiler and
the same applies to both?

Errrm subtitles anyone?

In many cases the cost of
installing is significantly more than
the cost of the boiler.



Absolute nonsense !!!!!


A bit out of touch I see...

If you go for two boilers on
different floors, then you also need to
find a place to install the second - in
many properties this is not a
trivial task.



You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant cylinder.


Assuming the cylinder was in the airing cupboard and not the loft... If
it is in an airing cupboard are you including the cost of providing
alternative heating for the cupboard since you are not going to get much
out of the casework of a decent condensing boiler?

Perhaps the OP would be better off installing a plain system boiler,
keeping the cylinder, and adding a shower pump...

You are going to be paying to have
two boilers serviced
annualy as well.



You can always get a deal with two boiers when they next to each other.


"OK mate I will only charge you twice the price to service them - five
quid discount since I will use less petrol..." (plus 20% hike to account
for the customer being a soft enough touch to fall for the two boilers gag)

--
Cheers,

John.

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  #19   Report Post  
John Rumm
 
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IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which is sad.


ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!

Here is a general challenge to the group - see if you can find a pair of
regular posters to this group, for which the above statement would be
*LESS* ironic!



--
Cheers,

John.

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\================================================= ================/
  #20   Report Post  
IMM
 
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"John Rumm" wrote in message
...
IMM wrote:

You clearly haven't a clue and lack
simple analytical skills. Which is sad.


And you have even less simple analytical skills.

snip tripe




  #21   Report Post  
IMM
 
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"John Rumm" wrote in message
...

snip tripe

It is like trying to explain matters to a 9 year old. It is best you just
take what I write as the correct way. Don't question it or you will be
confused as you are thinking.


  #22   Report Post  
Andy Hall
 
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On Wed, 31 Mar 2004 22:10:57 +0100, "IMM" wrote:




Read what I wrote above. It is clear.


With your writings, clarity is not a description
that I would use all that much.


You don't read properly. I am very clear.


Transparent in fact...



You can put them both together One,or both, can go at the back of the
airing cupboard, still releasing tons of space by the redundant

cylinder.

... needing a gas supply to be run there.....

Great thing eh!


It all adds to the cost.


Not much


Uh huh.



Nonsense again. No zone valves of any
sort would be in the system, either
externally or in the combi's. This make the
system as whole far more
reliable, with built-in redundancy.


What you are describing does not
equate to redundancy. You are
talking about a boiler per zone for heating
and hot water. Since you have described
these as being autonomous systems because of lack
of zone valves, it is not redundant in the least.


You will have heat in the house if one fails.


That is not redundancy.


Redundancy would happen if both
boilers were plumbed together in such
a way that one would take over from the
other in the event of failure


That can be dow by linking them up and having a full bore valve on the link.
One down turn it on by the valve and both are pumpoing into both rad
circuits. Cheap and simple.


Which involves links in the pipework between circuits etc....



Having HW and heating available in
only part of the house is not
redundancy, it's impaired service - not
the same thing at all..


Better than no heat at all. Simple to link them up. See above.



Why bother?

It's much more sensible just to buy good quality components and done
with it.




This solution is the one in question. You clearly cannot assess such a
system in cost, functionality and simplicity.


As you point out, it isn't rocket science.

However, as always, you are glossing over the details that will make
this harebrain scheme somewhat pointless.



I grew out of that attitude before my tenth birthday,


You must still be under 10 then.


I wish....



Read what I wrote again.
Read about the system and its advantages in:

- space saving,


compared to what? Certainly not one boiler.


snip garbage

You clearly haven't a clue and lack simple analytical skills. Which is sad.


I tend to be more left brained.



..andy

To email, substitute .nospam with .gl
  #23   Report Post  
John Rumm
 
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IMM wrote:

And you have even less simple analytical skills.


For once we are in total agreement ;-)

--
Cheers,

John.

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  #24   Report Post  
Andy Hall
 
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On Thu, 01 Apr 2004 01:13:35 +0100, John Rumm
wrote:

IMM wrote:

And you have even less simple analytical skills.


For once we are in total agreement ;-)


Nice.... ;-)



..andy

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  #25   Report Post  
IMM
 
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"Andy Hall" wrote in message
...

snip amateurish misinformed garbage




  #26   Report Post  
Ed Sirett
 
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On Wed, 31 Mar 2004 23:04:42 +0100, John Rumm wrote:

IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which is sad.


ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!


A number of us have tried the "let's explain this one step at a time
approach". Andy has a lot more faith/perserverance than others.
We have been around the loop with IMM a few times now over a number of
subjects, it's usually good for a laugh for everyone else.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at 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


  #27   Report Post  
geoff
 
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In message .uk, Ed
Sirett writes
On Wed, 31 Mar 2004 23:04:42 +0100, John Rumm wrote:

IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which is sad.


ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!


A number of us have tried the "let's explain this one step at a time
approach". Andy has a lot more faith/perserverance than others.
We have been around the loop with IMM a few times now over a number of
subjects, it's usually good for a laugh for everyone else.

It's certainly generated some good put down lines
--
geoff
  #28   Report Post  
IMM
 
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"geoff" wrote in message
...
In message .uk, Ed
Sirett writes
On Wed, 31 Mar 2004 23:04:42 +0100, John Rumm wrote:

IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which

is sad.

ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!


A number of us have tried the "let's explain this one step at a time
approach". Andy has a lot more faith/perserverance than others.
We have been around the loop with IMM a few times now over a number of
subjects, it's usually good for a laugh for everyone else.

It's certainly generated some good put down lines
--
geoff


Maxie, stick to looking at the pcb's.


  #29   Report Post  
IMM
 
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"Ed Sirett" wrote in message
news
On Wed, 31 Mar 2004 23:04:42 +0100, John Rumm wrote:

IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which is

sad.

ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!


A number of us have tried the "let's explain this one step at a time
approach". Andy has a lot more faith/perserverance than others.
We have been around the loop with IMM a few times now over a number of
subjects, it's usually good for a laugh for everyone else.


Stick to replacing the diverter valve on Vaillents. Best leave the thinking
to others.


  #30   Report Post  
Dave Plowman
 
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In article ,
Andy Hall wrote:
That is the point, it is cheap to install, with no zone valves, etc.


Zone valves are hardly expensive, are they?


'Zone valves, etc' require a basic understanding of electricity to
install. Guess why our resident 'expert' doesn't like them...

--
*Don't use no double negatives *

Dave Plowman London SW 12
RIP Acorn


  #31   Report Post  
John Rumm
 
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Dave Plowman wrote:

'Zone valves, etc' require a basic understanding of electricity to
install. Guess why our resident 'expert' doesn't like them...


It is interesting to watch in a way, but he seems to live in a world
totally governed by "rules of thumb". If he does not have one to hand
for the topic, then he will just grab one from the nearest web page, and
then cling to it for all he is worth, even when clearly it's way beyond
reason. I suppose it might be a result of a complete lack of analytical
/ scientific reason, or perhaps even a lack of basic mathematical
ability. Hence a rule of thumb is a simple way to overcome some of these
limitations that does not require taxing thought, vis:

Not able work out the actual pipe sizes required for your gas feed based
on flow resistances and pressure drops? apply rule "Install 22mm direct
to meter"

Don`t understand heat loss calcs? apply rule "you need 400mm of
insulation and tin foil under your tiles".

and so on...

Even uses if for politics: Difficulty applying observational reason or
historical precedent to political situations? apply rule of thumb "All
political ills can be solved by sticking with Tone"

Had you latest bright idea torn to shreds on usenet? apply rule "Snip
rational argument from post, and replace with insult or non sequitur,
hope no one notices!"


--
Cheers,

John.

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  #32   Report Post  
Andy Hall
 
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On Thu, 1 Apr 2004 23:50:38 +0100, "IMM" wrote:



Maxie, stick to looking at the pcb's.


The pcb's what?





..andy

To email, substitute .nospam with .gl
  #33   Report Post  
Andy Hall
 
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On Thu, 1 Apr 2004 23:51:53 +0100, "IMM" wrote:


"Ed Sirett" wrote in message
news
On Wed, 31 Mar 2004 23:04:42 +0100, John Rumm wrote:

IMM wrote:

You clearly haven't a clue and lack simple analytical skills. Which is

sad.

ROTFL

Watching Andy run (analytical) rings round IMM, is a spectacle I had
only previously observed in Road Runner cartoons!


A number of us have tried the "let's explain this one step at a time
approach". Andy has a lot more faith/perserverance than others.
We have been around the loop with IMM a few times now over a number of
subjects, it's usually good for a laugh for everyone else.


Stick to replacing the diverter valve on Vaillents. Best leave the thinking
to others.


.... and the spelling??



..andy

To email, substitute .nospam with .gl
  #34   Report Post  
IMM
 
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"John Rumm" wrote in message
...
Dave Plowman wrote:

'Zone valves, etc' require a basic understanding of electricity to
install. Guess why our resident 'expert' doesn't like them...


It is interesting


snip inane drivel


  #35   Report Post  
John Rumm
 
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IMM wrote:

snip inane drivel


I rest my case ;-)


--
Cheers,

John.

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  #36   Report Post  
IMM
 
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"John Rumm" wrote in message
...
IMM wrote:

snip inane drivel


I rest my case ;-)


How heavy is your case?


  #37   Report Post  
Nick Brooks
 
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IMM wrote:
"John Rumm" wrote in message
...

IMM wrote:


You clearly haven't a clue and lack
simple analytical skills. Which is sad.



And you have even less simple analytical skills.

snip tripe


Now I've seen it all, IMM has resorted to slagging himself off!!!
  #38   Report Post  
Nick Brooks
 
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John Rumm wrote:
IMM wrote:

snip inane drivel



I rest my case ;-)


The three above posts really did cause me to LOL making my colleagues
turn to look. I considered trying to explain the joke but rapidly
realised you had to be there.

Nick Brooks
  #39   Report Post  
IMM
 
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"Nick Brooks" wrote in message
...
IMM wrote:
"John Rumm" wrote in message
...

IMM wrote:

You clearly haven't a clue and lack
simple analytical skills. Which is sad.


And you have even less simple analytical skills.

snip tripe

Now I've seen it all, IMM has resorted to slagging himself off!!!


You have to learn how to read threads. The clinic can help you.


  #40   Report Post  
Lobster
 
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"IMM" wrote in message ...
"Andy Hall" wrote in message
...

snip amateurish misinformed garbage


Hah! that's you told, Andy... ;-)
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