On Mon, 18 May 2009 20:24:40 +0100, Owain wrote:

YAPH wrote:
looks smugly at "Bosch" name tag on boiler :-)

peels off "Bosch" name tag to reveal "Lucky Golden Hedgehog Warm
Cockles Make Happy Home"

Or maybe "Buderus": AIUI the kebab-shaped combustion chamber/heat exchanger
in the newer Worcester-Bosch Greenstar models was designed by Buderus who
were bought by W-B (or Bosch Thermotechnology or some part of the Bosch
empire).

--
John Stumbles -- http://yaph.co.uk

Seagull Management
Management technique characterised by flying in, making a lot of noise,
crapping on everything, and then leaving.

"Andy Champ" wrote in message
news
Mike Clarke wrote:

The extra efficiency is useful but the saving is quite small compared to
the
replacement cost. The existing boiler claims an efficiency ranging from
71%
at 9 KW up to 80% at 35 KW. A new combi with 90% efficiency might save 10
to 20% on the gas bill, last year's gas cost £520 so that could be a
saving
of about £50 to £100 per year - 10 to 20 years would be quite a long
payback time.


To get the 90% on the new one you may need new radiators to get the return
temperature low enough.

Or one with a clever control system that modulates the burner down when the
return temp is too high. Try a Broag with a weather compensator

"Mike Clarke" wrote in message
o.uk...
Dave Plowman (News) wrote:

In article ,
Mike Clarke wrote:
The extra efficiency is useful but the saving is quite small compared to
the replacement cost. The existing boiler claims an efficiency ranging
from 71% at 9 KW up to 80% at 35 KW. A new combi with 90% efficiency
might save 10 to 20% on the gas bill, last year's gas cost £520 so that
could be a saving of about £50 to £100 per year - 10 to 20 years would
be quite a long payback time.

That only works if you assume it will never need replacing.

Exactly, replacing a working boiler with
a condensing one just to reduce
energy costs will never make economic sense

You must stop making things up.

The message
from YAPH contains these words:

looks smugly at 30+ yr-old Glowworm back-boiler, still working fine :-)

looks smugly at gas bills for condensing boiler replacing 30~ yo
dinosaur :-)

So what exactly was replaced by what?

And by what percentage did the gas usage actually go down?

--
Roger Chapman

On Sun, 17 May 2009 11:53:27 +0100, "Dave Plowman (News)"
wrote:

In article ,
wrote:
Thus spake "Dave Plowman (News)" ) unto the assembled multitudes:

looks smugly at 30+ yr-old Glowworm back-boiler, still working fine

Wouldn't be too smug about the 50% efficiency, though. I'd say a
condensing boiler (especially if you can DIY) would soon recover its
cost.

I've been agonising about that for ages. Should I go for a new, more
efficient, lower carbon footprint condensing boiler that's going to
break down every few years (if I'm lucky) and need replacing after maybe
10 years, or stick with my old, inefficient boiler that just keeps going
and going with almost no maintenance - though as it's in my lounge I
would really quite like to get rid of it and install a proper hearth and
maybe a log burner.

Not all condensing boiler break down frequently - and like anything else
the cost of fixing them varies dramatically, including labour costs. My
Viessmann has a self diagnostic feature for any fault which may prove
useful.

Unless it is the self diagnostic feature that fails ;-)

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.

On 18 May 2009 20:58:46 GMT, YAPH wrote:

On Mon, 18 May 2009 14:22:54 +0000, A.Clews wrote:

The Bosch badge is no longer a guarantee.

thinks of mother's Bosch fridge/freezer which broke down beyond economic
repair at less than 3 years old

Long before we got to our current, third* Hotpoint F/F (the others having
broken down within months) I wished I'd bought the Bosch instead.

* 4th if you count the one we sent back because it was only a frost-free
fridge/freezer in the Hotpoint/Inde**** marketing weasels' Humpty-Dumpty
definition: if you want a real frost-free fridge/freezer, rather than a
frost-free freezer with a normal frost-prone fridge, you have to choose
what the weasels call a *fully* frost-free fridge freezer. Try saying that
in a hurry.

I wouldn't buy any kind of "frost free" freezer/fridge+freezer. They
are /much/ less reliable.

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.

In article ,
Roger wrote:
The message
from YAPH contains these words:

looks smugly at 30+ yr-old Glowworm back-boiler, still working
fine :-)

looks smugly at gas bills for condensing boiler replacing 30~ yo
dinosaur :-)

So what exactly was replaced by what?

And by what percentage did the gas usage actually go down?


I can give you my figures for changing from an RS BE cast iron
floorstander. 16% over this winter quarter - and it's been rather colder
than last year.

Only other change was going over to weather compensation from the previous
programmable roomstat. Still an open vented hot water storage system -
although the primary side is now sealed.

--
*I wish the buck stopped here. I could use a few.

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 19 May 2009 10:00:30 +0100, Mark wrote:

I wouldn't buy any kind of "frost free" freezer/fridge+freezer. They
are /much/ less reliable.

There's more in them to go wrong so I'd accept they're inherently likely
to be less reliable, but the extra bits are a fan, a motorised flap and a
heating element, none of which is exactly rocket science, so they shouldn't
be /much/ less reliable.


--
John Stumbles

Pessimists are never disappointed

On Tue, 19 May 2009 09:29:09 +0100, Roger wrote:

So what exactly was replaced by what?

Ideal Mexico BF by W-B Greenstar 24i Junior.

And by what percentage did the gas usage actually go down?

TBH I don't know: I wasn't keeping readings before and haven't done
since. The reason I junked the old boiler was that it kept falling over,
and the second time we came back from a few days away to a freezing cold
house because the pilot had died while we were away its card was marked.


--
John Stumbles -- http://yaph.co.uk

I can't stand intolerance

On Tue, 19 May 2009 10:25:54 +0100, Dave Plowman (News) wrote:

In article ,
Roger wrote:
The message from YAPH
contains these words:

looks smugly at 30+ yr-old Glowworm back-boiler, still working
fine :-)

looks smugly at gas bills for condensing boiler replacing 30~ yo
dinosaur :-)

So what exactly was replaced by what?

And by what percentage did the gas usage actually go down?


I can give you my figures for changing from an RS BE cast iron
floorstander. 16% over this winter quarter - and it's been rather colder
than last year.

Only other change was going over to weather compensation from the
previous programmable roomstat. Still an open vented hot water storage
system - although the primary side is now sealed.

That's about what I would expect from the boiler alone.

Changing from Non-independant HW cylinder heating and no TRVs and No wall
thermostat, no cylinder stat etc. would be a similar saving as well.


--
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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

In article , Ed Sirett
wrote:
Only other change was going over to weather compensation from the
previous programmable roomstat. Still an open vented hot water storage
system - although the primary side is now sealed.

That's about what I would expect from the boiler alone.

Changing from Non-independant HW cylinder heating and no TRVs and No
wall thermostat, no cylinder stat etc. would be a similar saving as
well.

Could you clarify, Ed? The Viessmann doesn't use a wall stat - but has a
cylinder one. I do have some TRVs. But not in the main heat demand area -
the living room.

--
*You're just jealous because the voices only talk to me *

Dave Plowman London SW
To e-mail, change noise into sound.

On 19 May 2009 13:13:50 GMT, John Stumbles
wrote:

On Tue, 19 May 2009 10:00:30 +0100, Mark wrote:

I wouldn't buy any kind of "frost free" freezer/fridge+freezer. They
are /much/ less reliable.

There's more in them to go wrong so I'd accept they're inherently likely
to be less reliable, but the extra bits are a fan, a motorised flap and a
heating element, none of which is exactly rocket science, so they shouldn't
be /much/ less reliable.

I agree that they shouldn't be much less reliable but they are.

Frost-free freezers also have a more complex control board which often
fails.

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.

Mark wrote:

I wouldn't buy any kind of "frost free" freezer/fridge+freezer. *They
are /much/ less reliable.

Well our 15 year old Bosch frost free fridge/freezer did have an initial
teething problem which was fixed under warranty. It's given 100% trouble
free service since then. We'd definitely go for another when it eventually
dies.

--
Mike Clarke

On Tue, 19 May 2009 17:51:40 +0100, Dave Plowman (News) wrote:

In article , Ed Sirett
wrote:
Only other change was going over to weather compensation from the
previous programmable roomstat. Still an open vented hot water
storage system - although the primary side is now sealed.

That's about what I would expect from the boiler alone.

Changing from Non-independant HW cylinder heating and no TRVs and No
wall thermostat, no cylinder stat etc. would be a similar saving as
well.

Could you clarify, Ed? The Viessmann doesn't use a wall stat - but has a
cylinder one. I do have some TRVs. But not in the main heat demand area
- the living room.

What I was saying was that the contribution to fuel saving from upgrading
a heating system is about 50:50 from boiler and the control upgrades.

Essentially, if you have the worst case system and go to current best
practice you should save about 30%. If you already have a good control
system then you should get about half of the improvement from just the
boiler. Which is what you got.

If you don't have some sort of overall temperature control on the space
heating then there is probably some more scope for saving.






--
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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

In article ,
Ed Sirett wrote:
Changing from Non-independant HW cylinder heating and no TRVs and No
wall thermostat, no cylinder stat etc. would be a similar saving as
well.

Could you clarify, Ed? The Viessmann doesn't use a wall stat - but has
a cylinder one. I do have some TRVs. But not in the main heat demand
area - the living room.

What I was saying was that the contribution to fuel saving from
upgrading a heating system is about 50:50 from boiler and the control
upgrades.

Essentially, if you have the worst case system and go to current best
practice you should save about 30%. If you already have a good control
system then you should get about half of the improvement from just the
boiler. Which is what you got.

If you don't have some sort of overall temperature control on the space
heating then there is probably some more scope for saving.

Think I am fairly up to date - but I'm confused about the

'Non-independant HW cylinder heating ---- no cylinder stat etc.' bit

- no mention of that in the Viessmann installation instructions. All I did
was change the stat on the cylinder for the Viessmann temperature sensor.

--
*Sometimes I wake up grumpy; Other times I let him sleep.

Dave Plowman London SW
To e-mail, change noise into sound.

"Ed Sirett" wrote in message
...

8

Could you clarify, Ed? The Viessmann doesn't use a wall stat - but has a
cylinder one. I do have some TRVs. But not in the main heat demand area
- the living room.

What I was saying was that the contribution to fuel saving from upgrading
a heating system is about 50:50 from boiler and the control upgrades.

Essentially, if you have the worst case system and go to current best
practice you should save about 30%. If you already have a good control
system then you should get about half of the improvement from just the
boiler. Which is what you got.

If you don't have some sort of overall temperature control on the space
heating then there is probably some more scope for saving.


IME the controls are more important than the type of boiler.

When I fitted my CH 28 years ago I put in one of the new fangled low water
content boilers with a copper heat exchanger (22 mm pipe with fins) and zone
valves with individual timers and stats.
My gas bill has always been less than half of the other identical houses
near me (the ones I know well enough to ask).

The insulation is so efficient that I turned the boiler output down to about
8kW and seldom need any extra heat (that doesn't stop the wife putting the
gas fire on even though it uses twice as much gas for the same heat out!).

The system is "on" 24x7x365 even in the summer.

I did the maths once to see if I should change the boiler.. the answer is a
definite no.
The one I have has a claimed efficiency of 82% so if I went to a condensing
one I would save about 12% which gives me a repayment period in excess of 10
years which appears to be longer than combies last..

You may like to know that the boiler is not modulating, it cycles quite
frequently as there is not much water in the system and there is usually
only one rad calling for heat when its on. It doesn't have much effect on
the amount of gas used but I have worn a gas valve out once in 28 years.

There is almost nothing in the boiler, a few stats, the gas valve, heat
exchanger and some pressed steel panels.

In article ,
dennis@home wrote:
When I fitted my CH 28 years ago I put in one of the new fangled low
water content boilers with a copper heat exchanger (22 mm pipe with
fins) and zone valves with individual timers and stats. My gas bill has
always been less than half of the other identical houses near me (the
ones I know well enough to ask).

That's because you keep your house much colder than they do - hence your
wife needed the gas fire on.

--
*The colder the X-ray table, the more of your body is required on it *

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 21 May 2009 09:01:37 +0100, Dave Plowman (News) wrote:

Think I am fairly up to date - but I'm confused about the

'Non-independant HW cylinder heating ---- no cylinder stat etc.' bit

I think Ed means a gravity HW system where the HW is heated any time the
CH is on (as well as when HW only is called for).


--
John Stumbles -- http://yaph.co.uk

My other sigs are posh

On Thu, 21 May 2009 09:17:57 +0100, dennis@home wrote:

The one I have has a claimed efficiency of 82%
....
There is almost nothing in the boiler, a few stats, the gas valve, heat
exchanger and some pressed steel panels.

Where is the 82% claimed? I'd expect a non-fanned boiler with a standing
pilot light to have considerably less efficiency than that measured
seasonally (i.e. SEDBUK).

--
John Stumbles -- http://yaph.co.uk

Things don't like being anthropomorphised.

"Dave Plowman (News)" wrote in message
...
In article ,
dennis@home wrote:
When I fitted my CH 28 years ago I put in one of the new fangled low
water content boilers with a copper heat exchanger (22 mm pipe with
fins) and zone valves with individual timers and stats. My gas bill has
always been less than half of the other identical houses near me (the
ones I know well enough to ask).

That's because you keep your house much colder than they do - hence your
wife needed the gas fire on.

I think she likes the glow.
Maybe my old 20" lcd and a fire video?

The message
from "Dave Plowman (News)" contains these words:

Changing from Non-independant HW cylinder heating and no TRVs and No
wall thermostat, no cylinder stat etc. would be a similar saving as
well.

Could you clarify, Ed? The Viessmann doesn't use a wall stat - but has a
cylinder one. I do have some TRVs. But not in the main heat demand area -
the living room.

How then do you maintain the desired temperature in the living room?

This is another repost so my apologies Dave if you saw the original and
decided not to bother but the message I posted yesterday still hasn't
appeared to me. Zetnet has gone to the dogs since they were taken over.

--
Roger Chapman

In article ,
Mark writes:
On 19 May 2009 13:13:50 GMT, John Stumbles
wrote:

On Tue, 19 May 2009 10:00:30 +0100, Mark wrote:

I wouldn't buy any kind of "frost free" freezer/fridge+freezer. They
are /much/ less reliable.

There's more in them to go wrong so I'd accept they're inherently likely
to be less reliable, but the extra bits are a fan, a motorised flap and a
heating element, none of which is exactly rocket science, so they shouldn't
be /much/ less reliable.

I agree that they shouldn't be much less reliable but they are.

Your basic sealed compressor and sealed tubing reached
astonishingly high levels of reliability, over 50 years
ago. It's pretty impossible to add anything to that
which doesn't rather dramaticly reduce the reliability.

Frost-free freezers also have a more complex control board which often
fails.

And several sensors, which also seem to fail too often.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]