"Malcolm Reeves" wrote in message
...
On Mon, 20 Sep 2004 17:43:57 +0100, "IMM" wrote:


"Malcolm Reeves" wrote in message
.. .
On Mon, 20 Sep 2004 14:04:41 +0100, "Neil Jones"
wrote:

Malcolm Reeves wrote:
On Sun, 19 Sep 2004 23:40:39 +0100, "IMM" wrote:


You should have TRV on at least all the bedroom rads which is the
new rules AFAIR.

Nothing says it is madatory in the regs.

Building regs part L 2002 guidelines say:

"If a whole heating system is replaced, the controls must permit
independent temperature control in two separate zones: the living
and
sleeping areas. This can be achieved with a single room thermostat
and
thermostatic radiator valves."

*can* be achieved...

It can also be achieved by using zoning with 2 thermostats or (I can't
believe I'm writing this) 2 boilers, one running the living areas, and
one for the bedrooms.

True, but as I read it the post was saying you didn't have to do that,
NOT, you didn't have to do that IF, you did something else.

It is mandatory to do some zone control

Where does it say that. A zone is an independently controlled, in time
and
temp, section of the heating system. A TVR does not converts a room into
a
zone.

- which for most TRVs are the
easiest route. The original poster
has TRVs AFAIR, I was just adding
that he needed to keep them.

Eh? I just quoted Building regs guide for part L above. That says
you have to do it which makes it mandatory. They are only considering
zones to be at different control temperatures not different on/off
times. But of course you can go that far if you want.

Vague. What is a zone. Anyone who knows heating will tell you a zones is "an
independently controlled, in time and temp, section of the heating system".

Like many of these regs they mean many things to different people.

On Mon, 20 Sep 2004 20:33:37 +0100, Andy Hall
wrote:

On Mon, 20 Sep 2004 20:29:52 +0100, Malcolm Reeves
wrote:



Eh? I just quoted Building regs guide for part L above. That says
you have to do it which makes it mandatory. They are only considering
zones to be at different control temperatures not different on/off
times. But of course you can go that far if you want.


The Approved Documents to the Building Regulations are not of
themselves legally binding. It says as much in the introduction of
most.

They represent *a* way of complying with the statute but are not the
*only* way.

If you can propose an alternative to the suggestion, this can be just
as valid, although it may be necessary to agree the point with the
BCO.

Read my post. I'm not saying you have to have TRVs but if the doc
says you have to have zones I don't see how you get around that (or
why you would want to). Yes, you can discuss things with the BCO and
he can sign off anything but realistically if it says zones you need
zones. A BCO is extremely unlikely to sign it off otherwise. And
zones being what the doc describes a minimum of temperature control.

Hells bells what is the problem. Has everyone taken argue pills or
something.


--

Malcolm

Malcolm Reeves BSc CEng MIEE MIRSE, Full Circuit Ltd, Chippenham, UK
, or ).
Design Service for Analogue/Digital H/W & S/W Railway Signalling and Power
electronics. More details plus freeware, Win95/98 DUN and Pspice tips, see:

http://www.fullcircuit.com or http://www.fullcircuit.co.uk

NEW - Desktop ToDo/Reminder program (free)

On Tue, 21 Sep 2004 08:19:42 +0100, Malcolm Reeves
wrote:

On Mon, 20 Sep 2004 20:33:37 +0100, Andy Hall
wrote:

On Mon, 20 Sep 2004 20:29:52 +0100, Malcolm Reeves
wrote:



Eh? I just quoted Building regs guide for part L above. That says
you have to do it which makes it mandatory. They are only considering
zones to be at different control temperatures not different on/off
times. But of course you can go that far if you want.


The Approved Documents to the Building Regulations are not of
themselves legally binding. It says as much in the introduction of
most.

They represent *a* way of complying with the statute but are not the
*only* way.

If you can propose an alternative to the suggestion, this can be just
as valid, although it may be necessary to agree the point with the
BCO.

Read my post. I'm not saying you have to have TRVs but if the doc
says you have to have zones I don't see how you get around that (or
why you would want to). Yes, you can discuss things with the BCO and
he can sign off anything but realistically if it says zones you need
zones. A BCO is extremely unlikely to sign it off otherwise. And
zones being what the doc describes a minimum of temperature control.

Hells bells what is the problem. Has everyone taken argue pills or
something.

I was simply pointing out that the Approved Documents are a guide and
nothing more than that. The methods described in the contents are not
mandatory

To quote

"Approved Documents are intended to provide guidance for some of the
more common building situations. However, there may well be
alternative ways of achieving compliance with the
requirements. Thus there is no obligation to adopt any particular
solution contained in an Approved Document if you prefer to meet the
relevant requirement in some other way."

Even in sections 1.38 and 1.39, the terms "would" and "could" are used
- not "shall"







..andy

To email, substitute .nospam with .gl

"Malcolm Reeves" wrote in message
...
On Mon, 20 Sep 2004 20:33:37 +0100, Andy Hall
wrote:

On Mon, 20 Sep 2004 20:29:52 +0100, Malcolm Reeves
wrote:



Eh? I just quoted Building regs guide for part L above. That says
you have to do it which makes it mandatory. They are only considering
zones to be at different control temperatures not different on/off
times. But of course you can go that far if you want.


The Approved Documents to the Building Regulations are not of
themselves legally binding. It says as much in the introduction of
most.

They represent *a* way of complying with the statute but are not the
*only* way.

If you can propose an alternative to the suggestion, this can be just
as valid, although it may be necessary to agree the point with the
BCO.

Read my post. I'm not saying you have to have TRVs but if the doc
says you have to have zones I don't see how you get around that (or
why you would want to).

It doesn't define what a zone is. Don't assume.

Yes, you can discuss things with the BCO and
he can sign off anything but realistically if it
says zones you need zones. A BCO is
extremely unlikely to sign it off otherwise. And
zones being what the doc describes a minimum
of temperature control.

Where does he accurately describe that?

Hells bells what is the problem.
Has everyone taken argue pills or
something.

Andy takes them all the time.

IMM wrote:


It doesn't define what a zone is. Don't assume.

Yes it does, in sections 1.38 and 1.39.

On Mon, 20 Sep 2004 10:25:39 +0100, Malcolm Reeves
wrote:

A condensing boiler with its lower flue gas temperature is much more
likely to accumulate fumes at low level (that's why they plume after
all). The advice on siting says to take account of the plume
possibility. My flue will face my neighbour. Do I want to risk the
possibility I might be dropping smelly fumes into his garden (and over
his washing line). For, perhaps GBP20 pa when I won't break even on
the boiler costs for 10yrs. NO.

Hi,

Why not make a stainless flue gas heat exchanger for a conventional
oil boiler, and use the low grade heat for UFH/HRV/DHW
preheat/kickspace heater?

I'd expect oil to increase in price over inflation in the next 10
years, this will speed up the payback on any up front investment.

cheers,
Pete.

"Neil Jones" wrote in message
...
IMM wrote:


It doesn't define what a zone is. Don't assume.

Yes it does, in sections 1.38 and 1.39.

They also say:

"Thus there is no obligation to adopt any particular solution contained in
an Approved Document if you prefer to meet the relevant requirement in some
other way."

IMM wrote:
"Neil Jones" wrote in message
...
IMM wrote:


It doesn't define what a zone is. Don't assume.

Yes it does, in sections 1.38 and 1.39.

They also say:

"Thus there is no obligation to adopt any particular solution
contained in an Approved Document if you prefer to meet the relevant
requirement in some other way."

This is the point I made earlier. It has nothing to do with whether or
not a 'zone' is defined.

They also say:

"Thus there is no obligation to adopt any particular solution contained in
an Approved Document if you prefer to meet the relevant requirement in
some
other way."

However, some people have a brain fart and interpret that to mean:

"Everything in this document is rubbish. You can make your walls out of
newspaper if you like."

They don't seem to understand that the "some other way" actually involves
ensuring similar energy savings/safety whatever and justifying it to the
BCO. If using some other method, you should be able to justify that the
proposed solution as at least as effective as the officially suggested one.

Christian.

On Tue, 21 Sep 2004 11:29:06 +0100, Pete C
wrote:

On Mon, 20 Sep 2004 10:25:39 +0100, Malcolm Reeves
wrote:

A condensing boiler with its lower flue gas temperature is much more
likely to accumulate fumes at low level (that's why they plume after
all). The advice on siting says to take account of the plume
possibility. My flue will face my neighbour. Do I want to risk the
possibility I might be dropping smelly fumes into his garden (and over
his washing line). For, perhaps GBP20 pa when I won't break even on
the boiler costs for 10yrs. NO.

Hi,

Why not make a stainless flue gas heat exchanger for a conventional
oil boiler, and use the low grade heat for UFH/HRV/DHW
preheat/kickspace heater?

Cos I'd need to convince Building control it was ok and given that
boiler is already about 90% efficient that only leaves 10% to get.
GBP40 pa tops. Not worth the effort. I could probably save more
shopping around for oil, improving insulation etc. It would be a very
risky endeavour with unknown gains.

I'd expect oil to increase in price over inflation in the next 10
years, this will speed up the payback on any up front investment.

Why? The US is wedded to the car. They drive everywhere and the
layout of their shops support that. If oil was more expensive so
would be US petrol. A much as I think they should pay more for petrol
to cut down their emissions I don't see it happening. Plus the last
time the Arab states hike petrol prices the world went into recession
which hit them too. Now they adopt a balancing act to get the biggest
income, that is the middle ground between cheap oil - large sales and
expensive oil - low sales. So why should oil increase in price? It
might fluctuate some, but that's all.


--

Malcolm

Malcolm Reeves BSc CEng MIEE MIRSE, Full Circuit Ltd, Chippenham, UK
, or ).
Design Service for Analogue/Digital H/W & S/W Railway Signalling and Power
electronics. More details plus freeware, Win95/98 DUN and Pspice tips, see:

http://www.fullcircuit.com or http://www.fullcircuit.co.uk

NEW - Desktop ToDo/Reminder program (free)

So why should oil increase in price? It might fluctuate some, but
that's all.

China.

Christian.

On Tue, 21 Sep 2004 18:21:11 +0100, Malcolm Reeves
wrote:

Why not make a stainless flue gas heat exchanger for a conventional
oil boiler, and use the low grade heat for UFH/HRV/DHW
preheat/kickspace heater?

Cos I'd need to convince Building control it was ok and given that
boiler is already about 90% efficient that only leaves 10% to get.
GBP40 pa tops. Not worth the effort. I could probably save more
shopping around for oil, improving insulation etc. It would be a very
risky endeavour with unknown gains.

Hi,

90% is very good for a non condensing boiler, though oil has half the
latent heat losses of natural gas.

One way to do it would be a fan assisted exchanger in parallel with
the flue, then there should be no net effect as the flow is balanced.

I'd expect oil to increase in price over inflation in the next 10
years, this will speed up the payback on any up front investment.

Why? The US is wedded to the car. They drive everywhere and the
layout of their shops support that. If oil was more expensive so
would be US petrol. A much as I think they should pay more for petrol
to cut down their emissions I don't see it happening. Plus the last
time the Arab states hike petrol prices the world went into recession
which hit them too. Now they adopt a balancing act to get the biggest
income, that is the middle ground between cheap oil - large sales and
expensive oil - low sales. So why should oil increase in price? It
might fluctuate some, but that's all.

I think it's their intention to get oil prices lower, but having tax
breaks for unnecessarily large vehicles won't help in the long run.

cheers,
Pete.

On Sat, 18 Sep 2004 16:17:55 +0100, "Tom"
wrote:

Most manufacturers seem to recommend setting flow rates in CH systems to
achieve a rise of 11deg across boiler, why is this? is it the most efficient
setting for heat transfer?
Tom

The straightforward answer to Tom's question, "11degC across Boiler,
why?" is that the 11 degree C is not a requirement at all. It is merely
the temperature rise from return to flow that the particular boiler can,
and does, achieve at the specified water flowrate when it is burning
flat out. Simple physics says that "Flow Rate X Temp Rise" is
proportional to "Heat Input X Boiler Efficiency".

The boiler is a heat source and so (obviously) generates a temperature
rise in the water flowing through it. The remainder of the system is a
heat dissipator and the temperature drop of the returning water is
determined by radiator sizes, room temperatures, air changes and so on.

A boiler can equally well operate at full output with a smaller rise, if
the system pumps at faster than the quoted rate, and conversely a lower
flow leads to a greater rise, possibly causing the limit stat to turn
off the burner, or turn it down if a modulator.

Radiators are also spec'd to give out their stated output at a certain
temperature drop and average temperature. This is commonly 11 degree C,
and is possibly the reason that so many believe that the drop is
'supposed to be' exactly that.

As has been mentioned in the thread above, systems can and are designed
for different flow/return temperatures to exploit the efficiency
characteristics of different systems. The actual temperature difference
the system uses depends on the c/h system designer's preferences as
admirably discussed above, and refers mainly to the case when the system
is going flat out in winter.

Phil
The uk.d-i-y FAQ is at http://www.diyfaq.org.uk/
Remove NOSPAM from address to email me

"Phil Addison" wrote in message
...
On Sat, 18 Sep 2004 16:17:55 +0100, "Tom"
wrote:

Most manufacturers seem to recommend setting flow rates in CH systems to
achieve a rise of 11deg across boiler, why is this? is it the most
efficient
setting for heat transfer?
Tom

The straightforward answer to Tom's question, "11degC across Boiler,
why?" is that the 11 degree C is not a requirement at all.

Read the installation instructions. That is what they say.

It is merely the temperature rise from return
to flow that the particular boiler can,
and does, achieve at the specified water flowrate when it is burning
flat out. Simple physics says that "Flow Rate X Temp Rise" is
proportional to "Heat Input X Boiler Efficiency".

The boiler is a heat source and so (obviously) generates a temperature
rise in the water flowing through it. The remainder of the system is a
heat dissipator and the temperature drop of the returning water is
determined by radiator sizes, room temperatures, air changes and so on.

A boiler can equally well operate at full output with a smaller rise, if
the system pumps at faster than the quoted rate, and conversely a lower
flow leads to a greater rise, possibly causing the limit stat to turn
off the burner, or turn it down if a modulator.

This tends to be the case with combi's in small flats. Most combi's can heat
a 5 bedroomed house. The modulation really helps. Early non-modulating
combi's cycled like crazy as the temp rise was far too great.

Radiators are also spec'd to give out their stated output at a certain
temperature drop and average temperature. This is commonly 11 degree C,
and is possibly the reason that so many believe that the drop is
'supposed to be' exactly that.

As has been mentioned in the thread above, systems can and are designed
for different flow/return temperatures to exploit the efficiency
characteristics of different systems. The actual temperature difference
the system uses depends on the c/h system designer's preferences as
admirably discussed above, and refers mainly to the case when the system
is going flat out in winter.

Phil
The uk.d-i-y FAQ is at http://www.diyfaq.org.uk/
Remove NOSPAM from address to email me

wrote:

Most manufacturers seem to recommend setting flow rates in CH systems to
achieve a rise of 11deg across boiler, why is this? is it the most
efficient
setting for heat transfer?
Tom
Thank you all for a magnificent response to my question, I understand a lot
more
now and I can see my way forward.
I'm most grateful to you.
Warm Regards
Tom