replacing c/heating boiler
 

i would like to replace my conventional boiler with a combination boiler has
anyone got inst instructions ?please

i would like to replace my conventional boiler with a combination boiler
has
anyone got inst instructions ?please

In order to fit gas appliances, you need to be what is described in the
legislation as a "competent person". For professional installation, this is
defined as being a member of CORGI, with, possibly an exception for BG.
However, for installations within your own home, it is permitted to DIY,
provided you can hold your head up high in a court of law and justify your
competence.

Unfortunately, the level of expertise that appears to be present from the
nature of your query would indicate that the court would be unlikely to
accept that you did comply with the competence requirement, and such an
installation would be illegal, and probably highly dangerous.

The court would be looking to ensure that you were able to perform and
understand all the calculations required to design the system. They would
also need to be convinced that your understood all the safety precautions
and systems required to do a professional installation.

Finally, the replacement of the boiler would come under building regulations
and require you to make a building application to your local authority to
ensure that the system as installed would comply with Part L1, for energy
efficiency and heating controls.

I would suggest ringing around in the Yellow Pages and asking for
recommendations for a CORGI installer in your local area. There is no need
to pay the high prices that BG and the other national companies charge.

Christian.

In message , Christian
McArdle writes
i would like to replace my conventional boiler with a combination boiler
has
anyone got inst instructions ?please

In order to fit gas appliances, you need to be what is described in the
legislation as a "competent person". For professional installation, this is
defined as being a member of CORGI, with, possibly an exception for BG.
However, for installations within your own home, it is permitted to DIY,
provided you can hold your head up high in a court of law and justify your
competence.

Just got into an argument with the chap in my local plumbers merchants
about this - I wanted a 1/4 inch iron plug to plug the end of the supply
pipe to gas fire I've removed.

'Is this for gas?'

'Yes'

'You have to be a member of CORGI etc.'

'Well actually you don't to DIY....'

'Oh yes you do....' and went a bit of spiel about it.

I waited to I got all my bits, before I tried to correct him, don't
think he believed me though.

Unfortunately, the level of expertise that appears to be present from the
nature of your query would indicate that the court would be unlikely to
accept that you did comply with the competence requirement,

Quite.

There is a bit in the uk.d-i-y FAQ about this.
--
Chris French, Leeds

In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Are you *sure* you want to do this, and have considered all the
implications?
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

In message , Set Square
writes

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Space was the short answer for us.

We replaced our boiler/HW tank system (the boiler was old and getting
knackered) with a combi.

We had a small bathroom , by getting rid of the tank and airing cupboard
we were able to put in decent separate shower, and rearrange things to
make a much better room. One advantage of the combi of course is we get
a good shower as well with no pumps etc.

Yes, I miss the airing cupboard at times, but I don't really miss the HW
tank that much. We are mostly shower people, and don't run baths very
often so the slow flow rate of the combi isn't to much of an issue - the
mains pressure HW is benefit. Multiple draw offs aren't a problem for
us.

It's not perfect, it's a compromise, but one that works ok for us.
--
Chris French, Leeds

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably *want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well known.

On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably *want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well known.

As are the disadvantages, such as the poor results when the available
water flow is poor.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well known.

As are the disadvantages, such as the poor results when the available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.

On Sat, 4 Sep 2004 10:28:46 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well known.

As are the disadvantages, such as the poor results when the available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.


Provided that the boiler is large enough for the application.



..andy

To email, substitute .nospam with .gl

In article ,
IMM wrote:
What a stupid question!! The advantages of combi boilers are well known.

Yup, they're cheap and easy to fit, so recommended by every plumber with
his eye on his profits.

--
*It is wrong to ever split an infinitive *

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

"IMM" wrote in message
...

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well known.


Well if taking three times as long to run a hot bath as would take using a
HW tank system (opposed to a mildly warm one given the same flow rate) is an
advantage.....

Just a real world example of a combi system that I came across the other day
whilst talking to some friends.

"Andy Hall" wrote in message
...
On Sat, 4 Sep 2004 10:28:46 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well
known.

As are the disadvantages, such as the poor results when the available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.


Provided that the boiler is large enough for the application.

Of course, that is stating the obvious. Why would you have one too small?
Do you buy a motor bike to transport a family around? No. You buy a 4/5
seater car.

In article ,
IMM wrote:
Provided that the boiler is large enough for the application.

Of course, that is stating the obvious. Why would you have one too
small? Do you buy a motor bike to transport a family around? No. You
buy a 4/5 seater car.

And all 4/5 seater cars are the same, and cost the same?

Most people buy the car they need for a specific purpose - and consider
the cost.

Just expecting a combi to do everything it should without considering the
possible upgrading cost of the incoming main(s) is rather like buying a
car without an engine...

--
*Is there another word for synonym?

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

On Sat, 4 Sep 2004 10:57:44 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 10:28:46 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well
known.

As are the disadvantages, such as the poor results when the available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.


Provided that the boiler is large enough for the application.

Of course, that is stating the obvious. Why would you have one too small?
Do you buy a motor bike to transport a family around? No. You buy a 4/5
seater car.


It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Sat, 4 Sep 2004 10:57:44 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 10:28:46 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...

However, I'm faced with the question "Why would anyone
conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well
known.

As are the disadvantages, such as the poor results when the
available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.

Provided that the boiler is large enough for the application.

Of course, that is stating the obvious. Why would you have one too
small?
Do you buy a motor bike to transport a family around? No. You buy a 4/5
seater car.

It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.

Because they shouldn't go to plumbers. They are useless. They should go to
heating engineers, who will know the market and what is available.

It is amazing how any people are delighted with correctly sized combi's.

On Sat, 4 Sep 2004 13:19:54 +0100, "IMM" wrote:



And when the available water flow is good, the advantages fly.

Provided that the boiler is large enough for the application.
wn.

As are the disadvantages, such as the poor results when the
availa
Of course, that is stating the obvious. Why would you have one too
small?
Do you buy a motor bike to transport a family around? No. You buy a 4/5
seater car.

It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.

Because they shouldn't go to plumbers. They are useless. They should go to
heating engineers, who will know the market and what is available.

It is amazing how any people are delighted with correctly sized combi's.


So are you a plumber or a heating engineer?


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Sat, 4 Sep 2004 13:19:54 +0100, "IMM" wrote:



And when the available water flow is good, the advantages fly.

Provided that the boiler is large enough for the application.
wn.

As are the disadvantages, such as the poor results when the
availa
Of course, that is stating the obvious. Why would you have one too
small?
Do you buy a motor bike to transport a family around? No. You buy a
4/5
seater car.

It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.

Because they shouldn't go to plumbers. They are useless. They should go
to
heating engineers, who will know the market and what is available.

It is amazing how any people are delighted with correctly sized combi's.

So are you a plumber or a heating engineer?

Is that Sarf Lahndan wit? Please advanced warning so people can laugh.

"IMM" wrote
| Provided that the boiler is large enough for the application.
| Of course, that is stating the obvious. Why would you have one
| too small? Do you buy a motor bike to transport a family around?
| No. You buy a 4/5 seater car.

Unless you're living in a Giles cartoon, who always manages to get a family
of six into a motorcycle er, er, er, *combination*. Back on topic after all.

Owain

On Sat, 4 Sep 2004 16:07:50 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 13:19:54 +0100, "IMM" wrote:



And when the available water flow is good, the advantages fly.

Provided that the boiler is large enough for the application.
wn.

As are the disadvantages, such as the poor results when the
availa
Of course, that is stating the obvious. Why would you have one too
small?
Do you buy a motor bike to transport a family around? No. You buy a
4/5
seater car.

It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.

Because they shouldn't go to plumbers. They are useless. They should go
to
heating engineers, who will know the market and what is available.

It is amazing how any people are delighted with correctly sized combi's.

So are you a plumber or a heating engineer?

Is that Sarf Lahndan wit?

I wouldn't know - I very seldom go there.

Please advanced warning so people can laugh.

No need really.


..andy

To email, substitute .nospam with .gl

On Fri, 03 Sep 2004 21:13:00 +0100, Set Square wrote:

In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas fitting -
so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Are you *sure* you want to do this, and have considered all the
implications?


To parody Fowler on the subject of split infinitives:

The combi questioner can be divided in several groups.

Firstly, those who neither know nor care.
These are the happiest of all especially if someone else pays the bills.

Secondly, those who don't know and do care.
They post to uk.d-i-y.

Thirdly, those who know and always approve.
We all know who he is.

Fourthly those who know and always condemn.
To those of you who are in this group I beg you to read on. I suspect
that this group is larger than it might otherwise be on account of two
factors. Firstly there are a proportion of professional installers who for
their own reasons prefer to always fit a combi regardless of the needs of
the customer. Secondly those in the third group whose style of advocacy could be
described as abrasive.


Fifthly those who know and discrimate.
There are quite a number of criteria which have to be considered.
User's infomred preferences.
User's previous experience.
User's prejudice.
Size of dwelling: Space v. cylinder benfits.
User's HW usage patterns.
Instant Availability v. Storage heat losses.
Number and size of simultaneous or back-to-back HW demands
(Showers v. baths.)
Quality of mains supply.
Pre-Existing arrangements and cost implications.
...



--
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

In an earlier contribution to this discussion,
Ed Sirett wrote:

On Fri, 03 Sep 2004 21:13:00 +0100, Set Square wrote:

In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting - so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want* to replace a conventional boiler with a combi?"

Are you *sure* you want to do this, and have considered all the
implications?


To parody Fowler on the subject of split infinitives:

The combi questioner can be divided in several groups.

Firstly, those who neither know nor care.
These are the happiest of all especially if someone else pays the
bills.

Secondly, those who don't know and do care.
They post to uk.d-i-y.

Thirdly, those who know and always approve.
We all know who he is.

Fourthly those who know and always condemn.
To those of you who are in this group I beg you to read on. I suspect
that this group is larger than it might otherwise be on account of two
factors. Firstly there are a proportion of professional installers
who for their own reasons prefer to always fit a combi regardless of
the needs of
the customer. Secondly those in the third group whose style of
advocacy could be described as abrasive.


Fifthly those who know and discrimate.
There are quite a number of criteria which have to be considered.
User's infomred preferences.
User's previous experience.
User's prejudice.
Size of dwelling: Space v. cylinder benfits.
User's HW usage patterns.
Instant Availability v. Storage heat losses.
Number and size of simultaneous or back-to-back HW demands
(Showers v. baths.)
Quality of mains supply.
Pre-Existing arrangements and cost implications.
...

I'm not sure into which category I'm deemed to fall, having questioned the
wisdom of converting to a combi!

Although I have a bias against combis in principle, there are circumstances
where they are appropriate - when starting with a clean sheet. For example,
my 95-year-old father-in-law lives in a bungalow which is heated by electric
storage heaters, with the hot water being heated by an immersion heater. I
would desperately like him to ditch the storage heaters and go for a decent
gas-fired heating and hot water system. [Gas *is* available, even though he
doesn't currently use it]. A combi would suit him down to the ground.

However, in cases where a system already exists - using a conventional
boiler and stored hot water - there would, in my view, have to be some
pretty exceptional circumstances to warrant converting to a combi-based
system.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

On Sat, 04 Sep 2004 23:03:38 +0100, Set Square wrote:

In an earlier contribution to this discussion,
Ed Sirett wrote:

On Fri, 03 Sep 2004 21:13:00 +0100, Set Square wrote:

In an earlier contribution to this discussion,
Jentrev96 wrote:

i would like to replace my conventional boiler with a combination
boiler has anyone got inst instructions ?please

Others have already commented on competence issues related to gas
fitting - so I won't repeat all that.

However, I'm faced with the question "Why would anyone conceivably
*want* to replace a conventional boiler with a combi?"

Are you *sure* you want to do this, and have considered all the
implications?


To parody Fowler on the subject of split infinitives:

The combi questioner can be divided in several groups.

Firstly, those who neither know nor care.
These are the happiest of all especially if someone else pays the
bills.

Secondly, those who don't know and do care.
They post to uk.d-i-y.

Thirdly, those who know and always approve.
We all know who he is.

Fourthly those who know and always condemn.
To those of you who are in this group I beg you to read on. I suspect
that this group is larger than it might otherwise be on account of two
factors. Firstly there are a proportion of professional installers
who for their own reasons prefer to always fit a combi regardless of
the needs of
the customer. Secondly those in the third group whose style of
advocacy could be described as abrasive.


Fifthly those who know and discrimate.
There are quite a number of criteria which have to be considered.
User's infomred preferences.
User's previous experience.
User's prejudice.
Size of dwelling: Space v. cylinder benfits.
User's HW usage patterns.
Instant Availability v. Storage heat losses.
Number and size of simultaneous or back-to-back HW demands
(Showers v. baths.)
Quality of mains supply.
Pre-Existing arrangements and cost implications.
...

I'm not sure into which category I'm deemed to fall, having questioned the
wisdom of converting to a combi!

Although I have a bias against combis in principle, there are circumstances
where they are appropriate - when starting with a clean sheet. For example,
my 95-year-old father-in-law lives in a bungalow which is heated by electric
storage heaters, with the hot water being heated by an immersion heater. I
would desperately like him to ditch the storage heaters and go for a decent
gas-fired heating and hot water system. [Gas *is* available, even though he
doesn't currently use it]. A combi would suit him down to the ground.

However, in cases where a system already exists - using a conventional
boiler and stored hot water - there would, in my view, have to be some
pretty exceptional circumstances to warrant converting to a combi-based
system.

A typical dwelling where a combi might well be the best approach is:

A 1 bed flat built in 1975 which has a Arcopack (sp?) and a life expired
conventional boiler.
The Arcopack unit is pre-plumbed steel contraption with a steel CW
cistern and an insulated copper HW tank/cylinder) in the lower section.
Typically a small F&E header tank is provided inside the upper part of the
cistern for the primary circuit.
Flow rates to the bath are moderate and there is no (I don't mean little)
pressure for a shower.

The mains is plastic but only 1/2"/20mm. Good enough for a combi but
debatable for unvented.

The cupboard space is relatively more valuable in a small flat. The
maximum occupation is likely to be a couple + very small kid.

You will not likely rent out any such flat in the middle market private
sector without a shower.

The combi will only be a little larger than the old boiler.

Booster pumps can cause noise problems leading to serious conflict between
neighbours.

The case for a combi is fairly strong in the above scenario.

--
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

In an earlier contribution to this discussion,
Ed Sirett wrote:

On Sat, 04 Sep 2004 23:03:38 +0100, Set Square wrote:


However, in cases where a system already exists - using a
conventional boiler and stored hot water - there would, in my view,
have to be some pretty exceptional circumstances to warrant
converting to a combi-based system.

A typical dwelling where a combi might well be the best approach is:

A 1 bed flat built in 1975 which has a Arcopack (sp?) and a life
expired conventional boiler.
The Arcopack unit is pre-plumbed steel contraption with a steel CW
cistern and an insulated copper HW tank/cylinder) in the lower
section. Typically a small F&E header tank is provided inside the
upper part of the cistern for the primary circuit.
Flow rates to the bath are moderate and there is no (I don't mean
little) pressure for a shower.

The mains is plastic but only 1/2"/20mm. Good enough for a combi but
debatable for unvented.

The cupboard space is relatively more valuable in a small flat. The
maximum occupation is likely to be a couple + very small kid.

You will not likely rent out any such flat in the middle market
private sector without a shower.

The combi will only be a little larger than the old boiler.

Booster pumps can cause noise problems leading to serious conflict
between neighbours.

The case for a combi is fairly strong in the above scenario.


Agreed - there will be specific (dare I say "exceptional"?) circumstances
where a combi is the appropriate solution.

However, *in general*, I believe that replacing a conventional boiler with a
combi *doesn't* make sense.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

On Sun, 05 Sep 2004 22:18:04 +0100, Set Square wrote:

In an earlier contribution to this discussion,
Ed Sirett wrote:

On Sat, 04 Sep 2004 23:03:38 +0100, Set Square wrote:


However, in cases where a system already exists - using a
conventional boiler and stored hot water - there would, in my view,
have to be some pretty exceptional circumstances to warrant
converting to a combi-based system.

A typical dwelling where a combi might well be the best approach is:

A 1 bed flat built in 1975 which has a Arcopack (sp?) and a life
expired conventional boiler.
The Arcopack unit is pre-plumbed steel contraption with a steel CW
cistern and an insulated copper HW tank/cylinder) in the lower
section. Typically a small F&E header tank is provided inside the
upper part of the cistern for the primary circuit.
Flow rates to the bath are moderate and there is no (I don't mean
little) pressure for a shower.

The mains is plastic but only 1/2"/20mm. Good enough for a combi but
debatable for unvented.

The cupboard space is relatively more valuable in a small flat. The
maximum occupation is likely to be a couple + very small kid.

You will not likely rent out any such flat in the middle market
private sector without a shower.

The combi will only be a little larger than the old boiler.

Booster pumps can cause noise problems leading to serious conflict
between neighbours.

The case for a combi is fairly strong in the above scenario.


Agreed - there will be specific (dare I say "exceptional"?) circumstances
where a combi is the appropriate solution.

However, *in general*, I believe that replacing a conventional boiler with a
combi *doesn't* make sense.

You may well be right. Perhaps I see a somewhat skewed picture of UK
housing since a big part of my work is middle to up market private rented
flats.

--
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

On Fri, 3 Sep 2004 23:28:50 +0100, chris French
wrote:

In message , Set Square
writes

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Space was the short answer for us.

We replaced our boiler/HW tank system (the boiler was old and getting
knackered) with a combi.

We had a small bathroom , by getting rid of the tank and airing cupboard
we were able to put in decent separate shower, and rearrange things to
make a much better room. One advantage of the combi of course is we get
a good shower as well with no pumps etc.

Yes, I miss the airing cupboard at times, but I don't really miss the HW
tank that much. We are mostly shower people, and don't run baths very
often so the slow flow rate of the combi isn't to much of an issue - the
mains pressure HW is benefit. Multiple draw offs aren't a problem for
us.

Okay, it's time for a complete CH novice to butt in here and ask a few
questions, as gas heating boilers may well be of interest to me soon.

What is a combi boiler and how does it differ from a conventional
boiler?

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

What are the fundamental differences in two properties' heating
systems, one with a conventional boiler, and the other with a combi
boiler?

MM

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

The difference between the (instantaneous) combi and the non-combi boiler is
that the combi boiler has a heat exchanger that heats the incoming cold
water as you need it. It does this without any tanks or hot or cold water
storage. Advantages are that it uses the full mains pressure, so you get
excellent showers (assuming a reasonable water supply). Unfortunately, it
will heat only so much water at a time, so bath filling tends to be slow.
They are a good choice for houses where the bath is used infrequently, as
they are cheaper, smaller and more efficient than a storage based solution.

It gets rid of the external pump, because they almost invariably have an
internal one, making the external one redundant. Even most non-combi boilers
have a built in pump these days.

Christian.

On Tue, 7 Sep 2004 09:34:46 +0100, "Christian McArdle"
wrote:

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

The difference between the (instantaneous) combi and the non-combi boiler is
that the combi boiler has a heat exchanger that heats the incoming cold
water as you need it. It does this without any tanks or hot or cold water
storage. Advantages are that it uses the full mains pressure, so you get
excellent showers (assuming a reasonable water supply). Unfortunately, it
will heat only so much water at a time, so bath filling tends to be slow.
They are a good choice for houses where the bath is used infrequently, as
they are cheaper, smaller and more efficient than a storage based solution.

It gets rid of the external pump, because they almost invariably have an
internal one, making the external one redundant. Even most non-combi boilers
have a built in pump these days.

Christian.

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

MM

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you have
one daily, you may find the wait too long, unless you develop a habit, such
as getting breakfast whilst it is filling.

Christian.

Christian McArdle wrote:

[Combi-boilers] will heat only so much water at a time, so bath
filling tends to be slow. They are a good choice for houses where
the bath is used infrequently, as they are cheaper, smaller and more
efficient than a storage based solution.

I know Christian knows this, but to help clarify:

They are a good choice for houses where the bath is used
infrequently, or where bath-taking is seen as a slow, relaxing
affair and the 10-15 minutes to fill one can be taken to prepare
oneself for having a bath (this seems to take Mrs Socks about 25-30
minutes, so 10-15 minutes of that time simultaniously having the
bath filling isn't a problem!).
--
Selah

On Tue, 7 Sep 2004 09:56:44 +0100, "Christian McArdle"
wrote:

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you have
one daily, you may find the wait too long, unless you develop a habit, such
as getting breakfast whilst it is filling.

Christian.

... and using it after lunch :-)


..andy

To email, substitute .nospam with .gl

On Tue, 07 Sep 2004 07:33:24 +0100, Mike Mitchell wrote:

On Fri, 3 Sep 2004 23:28:50 +0100, chris French
wrote:

In message , Set Square
writes

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Space was the short answer for us.

We replaced our boiler/HW tank system (the boiler was old and getting
knackered) with a combi.

We had a small bathroom , by getting rid of the tank and airing cupboard
we were able to put in decent separate shower, and rearrange things to
make a much better room. One advantage of the combi of course is we get
a good shower as well with no pumps etc.

Yes, I miss the airing cupboard at times, but I don't really miss the HW
tank that much. We are mostly shower people, and don't run baths very
often so the slow flow rate of the combi isn't to much of an issue - the
mains pressure HW is benefit. Multiple draw offs aren't a problem for
us.

Okay, it's time for a complete CH novice to butt in here and ask a few
questions, as gas heating boilers may well be of interest to me soon.

What is a combi boiler and how does it differ from a conventional
boiler?

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

What are the fundamental differences in two properties' heating
systems, one with a conventional boiler, and the other with a combi
boiler?

See main FAQ. And the other ones too.


--
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

On Tue, 07 Sep 2004 11:01:04 +0100, Andy Hall wrote:

On Tue, 7 Sep 2004 09:56:44 +0100, "Christian McArdle"
wrote:

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you have
one daily, you may find the wait too long, unless you develop a habit, such
as getting breakfast whilst it is filling.

Christian.

.. and using it after lunch :-)

If the bath is a small swimming pool. :-)


--
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

"Ed Sirett" wrote in message
n.co.uk...
On Tue, 07 Sep 2004 11:01:04 +0100, Andy Hall wrote:

On Tue, 7 Sep 2004 09:56:44 +0100, "Christian McArdle"
wrote:

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you
have
one daily, you may find the wait too long, unless you develop a habit,
such
as getting breakfast whilst it is filling.

Christian.

.. and using it after lunch :-)

If the bath is a small swimming pool. :-)

Or other small pool occasionally found indoors ;-)

Mike Mitchell wrote in message . ..
On Fri, 3 Sep 2004 23:28:50 +0100, chris French
wrote:

In message , Set Square
writes

However, I'm faced with the question "Why would anyone conceivably *want* to
replace a conventional boiler with a combi?"

Space was the short answer for us.

We replaced our boiler/HW tank system (the boiler was old and getting
knackered) with a combi.

We had a small bathroom , by getting rid of the tank and airing cupboard
we were able to put in decent separate shower, and rearrange things to
make a much better room. One advantage of the combi of course is we get
a good shower as well with no pumps etc.

Yes, I miss the airing cupboard at times, but I don't really miss the HW
tank that much. We are mostly shower people, and don't run baths very
often so the slow flow rate of the combi isn't to much of an issue - the
mains pressure HW is benefit. Multiple draw offs aren't a problem for
us.

Okay, it's time for a complete CH novice to butt in here and ask a few
questions, as gas heating boilers may well be of interest to me soon.

What is a combi boiler and how does it differ from a conventional
boiler?

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

What are the fundamental differences in two properties' heating
systems, one with a conventional boiler, and the other with a combi
boiler?

IMM did an excellent post on the differnt types of combi's. Do a
Google. I did a Google on Alpha CB50 and it came up. Read this first
before you go any futher.

Mike Mitchell wrote in message . ..
On Tue, 7 Sep 2004 09:34:46 +0100, "Christian McArdle"
wrote:

I have an airing cupboard, a hot water tank and my boiler has a pump.
How/why does the combi boiler get rid of both the latter?

The difference between the (instantaneous) combi and the non-combi boiler is
that the combi boiler has a heat exchanger that heats the incoming cold
water as you need it. It does this without any tanks or hot or cold water
storage. Advantages are that it uses the full mains pressure, so you get
excellent showers (assuming a reasonable water supply). Unfortunately, it
will heat only so much water at a time, so bath filling tends to be slow.
They are a good choice for houses where the bath is used infrequently, as
they are cheaper, smaller and more efficient than a storage based solution.

It gets rid of the external pump, because they almost invariably have an
internal one, making the external one redundant. Even most non-combi boilers
have a built in pump these days.

Christian.

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

MM

There are higher water flow combi's around. The Alpha CB50 I mentioned
in my last post is one. The larger combi's fill baths as fast as any
storage system and are far easier to fit and get rid of tanks. I know
of a few higher water flow combi's and the owners would not have
anything else. Don't buy the small flow rate combi's, get a large flow
model if you want fast filling baths.

In article ,
timegoesby wrote:
There are higher water flow combi's around. The Alpha CB50 I mentioned
in my last post is one. The larger combi's fill baths as fast as any
storage system and are far easier to fit and get rid of tanks. I know
of a few higher water flow combi's and the owners would not have
anything else. Don't buy the small flow rate combi's, get a large flow
model if you want fast filling baths.

You are IMM and I claim my 5 pounds.

--
*With her marriage she got a new name and a dress.*

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

Andy Hall wrote in message . ..
On Sat, 4 Sep 2004 10:57:44 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 10:28:46 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sat, 4 Sep 2004 09:47:00 +0100, "IMM" wrote:


"Set Square" wrote in message
...

However, I'm faced with the question "Why would anyone conceivably
*want*
to
replace a conventional boiler with a combi?"

What a stupid question!! The advantages of combi boilers are well
known.

As are the disadvantages, such as the poor results when the available
water flow is poor.

As with any mains fed system.

And when the available water flow is good, the advantages fly.


Provided that the boiler is large enough for the application.

Of course, that is stating the obvious. Why would you have one too small?
Do you buy a motor bike to transport a family around? No. You buy a 4/5
seater car.


It is, but it is surprising how many people have 9lpm combis and 9lpm
water supplies and are disappointed.


.andy

To email, substitute .nospam with .gl


Combis are like that other favourute, hot air heating. It's so easy to
end up with a bad installation. I have yet to come across a combi
(thankfully I have only had experience of 5) which performs well
either in terms of flow rate or temperature stabilty when other taps
are opened/closed.

MBQ

"Christian McArdle" wrote:

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you have
one daily, you may find the wait too long, unless you develop a habit, such
as getting breakfast whilst it is filling.

Christian.

But this is just not true for most decent combis. Here, I live in a
tank system house. The hot water is a hot dribble really, the pump is
only used for the shower and sounds as if I have a Moto Guzzi in the
house. While I have seen combis in various locations in the UK where
the hot water at mains pressure. This results in a high flow at least
in areas suitable for combis, not to true for other areas where combis
should not be installed - ask your plumber. I usually take a bath
after doing the dishes in the evening, my bloody tank is not big
enough and with the heating on, it takes forever and a bit to fill the
tank. Not an issue with the combi, where hot water is on demand.

No guys, where combis can be done (depending on mains pressure), they
usually beat a comparable tank system flat out. Well, to be honest, I
have never seen a new tank system, but plenty of new combi systems
here. And the thing with the cold water tanks in the loft dribbling
through your house makes you feel as if your buddy has a chronic
prostate problem ;-) Oh and for hygienic apostles amongst us all, take
a look in the cold water tank, then think about the hot water tank,
where hot water stays for days. And then count the bacteria. A combi
basically serves up drinking water (well, I would still not use it for
tea though ;-))

Right. Final issue: water temperature. The combi's performance depends
on the distance between boiler and bath. The closer the hotter the
water. The tank has the same issue (hence its usual location in the
bathroom) but, BUT, a mildly old tank system will loose heat = the hot
water is not of the same temperature. Kind of sucks when you keep your
hot water at a low temperature only to find out that your bath is
lukewarm because the water was sitting in the tank for a day or so.

I know it comes down to personal preference, but don't sell combis as
having problems to fill a bath. With any decent combi that just is not
the issue.

Fred

In article ,
Fred wrote:
No guys, where combis can be done (depending on mains pressure), they
usually beat a comparable tank system flat out. Well, to be honest, I
have never seen a new tank system, but plenty of new combi systems
here.

You've not seen a reasonably well done storage system either. Like
everything, it requires care and skill to install - more than an
equivalent high pressure system since poor pipework will restrict the flow
more.

--


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

On Fri, 10 Sep 2004 16:56:07 +0000 (UTC), (Fred)
wrote:

"Christian McArdle" wrote:

Ah, right. I couldn't do without my baths, though! I lived with a
shower for 12 years (i.e. no bath) and the joy of a relaxing, piping
hot bath, especially on a cold winter's morning, is irreplaceable.

Don't get me wrong. They will still fill a bath. It's just that if you have
one daily, you may find the wait too long, unless you develop a habit, such
as getting breakfast whilst it is filling.

Christian.

But this is just not true for most decent combis. Here, I live in a
tank system house. The hot water is a hot dribble really, the pump is
only used for the shower and sounds as if I have a Moto Guzzi in the
house.

Then you didn't have the tank system fitted properly because it's
easily possible to have a substantial flow.

If your pump makes a lot of noise, you either bought a cheap one or it
wasn't fitted properly.



While I have seen combis in various locations in the UK where
the hot water at mains pressure. This results in a high flow at least
in areas suitable for combis, not to true for other areas where combis
should not be installed - ask your plumber. I usually take a bath
after doing the dishes in the evening, my bloody tank is not big
enough and with the heating on, it takes forever and a bit to fill the
tank. Not an issue with the combi, where hot water is on demand.

No guys, where combis can be done (depending on mains pressure), they
usually beat a comparable tank system flat out.

That is demonstrably nonsense. There is no physical way that even
quite a large combi system can deliver hot water at a greater rate
than a tank storage system provided that the pipework is adequate on
the storage system.

Well, to be honest, I
have never seen a new tank system, but plenty of new combi systems
here. And the thing with the cold water tanks in the loft dribbling
through your house makes you feel as if your buddy has a chronic
prostate problem ;-) Oh and for hygienic apostles amongst us all, take
a look in the cold water tank, then think about the hot water tank,
where hot water stays for days. And then count the bacteria.

If the hot water cylinder stores the water at 60 degrees there will
not be a bacteria problem.


A combi
basically serves up drinking water (well, I would still not use it for
tea though ;-))

Right. Final issue: water temperature. The combi's performance depends
on the distance between boiler and bath. The closer the hotter the
water. The tank has the same issue (hence its usual location in the
bathroom) but, BUT, a mildly old tank system will loose heat = the hot
water is not of the same temperature. Kind of sucks when you keep your
hot water at a low temperature only to find out that your bath is
lukewarm because the water was sitting in the tank for a day or so.

This is complete nonsense.

The rate of water production from a combi is *highly* dependent on the
incoming water temperature and the flow rate.
This is not the case where the DHW is stored.

Neither will give any significant temperature drop between the point
of heating and point of delivery in a normal house.



I know it comes down to personal preference, but don't sell combis as
having problems to fill a bath. With any decent combi that just is not
the issue.

A combi is suitable for a flat or very small house, or where the
occupants have modest requirements for hot water delivery.

For a 3-4 bedroom house wiht multiple occupants, the performance
becomes increasingly inferior to storage. Storage can be by directly
storing the DHW in a cylinder, or via a heatbank, but is the only way
to get good results where multiple bathrooms are in use.




Fred

..andy

To email, substitute .nospam with .gl