Siting of a replacement boiler

[jdey]

As some of you know, I have an old-fashioned Servowarm Supreme radiator back boiler whose flue is currently located at the front of my house to the left of the front door. The guy that came around yesterday seemed intent on putting the new boiler in the kitchen or bathroom, and I was curious why.

Looking at the ODPM site for the building regulations, it looks like boilers are no longer allowed in living rooms. Is this the case, or am I misreading it? http://www.odpm.gov.uk/pub/731/Guid...tProcedureforDwellingsPDF1258Kb_id1130731.pdf

I currently have 2 seperate systems, which I want to maintain. The hot water system runs along the external walls of the kitchen & bathroom with the instant heat boiler being located in the bathroom. The heating system runs along the internal walls of the kitchen & bathroom. As I understand it, a condensing boiler has to be on an external wall, so this would incur a problem in that connections would then have to somehow move from the external wall to connect up with the previous pipework. I can't see how this would easily be achieved, as my bathroom is tiled and my kitchen has a brand new wooden floor, which would need to be lifted.

Another question that I have is that I've read that condensing boilers used to have a very short life time as the acidic concentrate corroded the heat exchangers, but this has been solved by making the heat exchangers from stainless steel. Is this true or not?

Any suggestions most welcome.

 

[Paul Barker]

No you don't have to use stainless steel, you just have to design things correctly. The former steamers sold to and in UK were badly designed. There always have been and remain some excellent condensing boilers, and now the bad manufacturers are catching up also bceause of the sheer numbers now on sale.

Keep the mulitpoint.

Take heating pipes across floor of room above kitchen.

 

[jdey]

Thanks. Does this mean that I can't put the new condensing boiler in the existing living room site?

 

[Prof.plumb]

Let me just explain the current situation with boilers. Since april last year there was a government drive to fit only efficient appliances, whether it be a washing machine or a boiler. however, where boilers were concerned the most efficient boilers available are condensing boilers. Theses come under 2 bands. Band A and band B.
It is now law for an installer to fit a condensing boiler where possible. The exceptions are: if you can not gain the 600mm termination to a boundary line (this is changing to 2.5m), you can fit a standard efficiency boiler. And if you have a back boiler and fire you can still fit a replacement back boiler and fire. In your case you should do this as it will work out cheaper.
A couple of things to bear in mind. When your installer fits a new boiler he must bring the rest of the system up to part L compliance. SO you should have rad stats on rads in atleast the bedrooms. And you should have a room stat fitted too. Furthermore you should have motorised valves fitted to give you control over heating and hot water.

 

[ChrisR]

And if you have a back boiler and fire you can still fit a replacement back boiler and fire.

Think you'll find that's not right!

The odpm rules are of course incompetently written - so what's new?

Take
"Your task is to find the lowest cost option (given by the lowest number of points) for installing a condensing boiler,"
Drivel. Cost and points are not related.

Where the "boiler... not to be considered for installation.. in room of primary occupation..." stuff comes from I have no idea. Plenty ARE in living rooms.
Boiler Mfrs Instrs never preclude living room installations.

The flue/plume is more likely to be a problem perhaps.

 

[jdey]

thanks. There seems to be quite a room for maneouvre in the guidance provided by the ODPM to meet the building regs. If a CORGI engineer signs the assessment form indicating that it's uneconomic to put a new condensing boiler in the kitchen/bathroom and signs the building regs certificate, is this sufficient, or can the Local Authority challenge this decision? I'm worried what would happen when I move house.

In terms of other things which need to be added to the system to meet part L, I can find summary info indicating that a room thermostat is required but can't find anything which indicates a necessity for TRVs on some/all rads. Do you have a weblink reference that I can look at?

 

[jdey]

My situation is:-

1. I've got no drains upstairs so the condensing boiler can't go upstairs
2. I've got my instant hot water boiler in the bathroom, and the rest of the bathroom is tiled, so it wouldn't be economical to put it there
3. The only space against an external wall in the kitchen would be infront of the bathroom door.
4. The guidance seems to indicate that a condensing boiler isn't allowed in a principle living room, which is where my existing boiler is sited, and if it were it would be pumping out steam to the left of my front door, although I do have a patioed front garden so it wouldn't pump out on to the street.
5. My existing boiler is hidden underneath and behind a radiator. I'm not sure what the technical definition of this type of boiler is. I'd call it a floor standing integrated radiator boiler.

It seems that each plumber has a different interpretation of the rules, and I can't seem to find the amendment to section L of the Building Regs which gives the definitive answer.

 

[ChrisR]

If a CORGI engineer signs the assessment form indicating that it's uneconomic

He won't. My edit to my previous post was while you were writing..

Cost doesn't come into it. It's very unlikely that your abode will be one which could be exempt from the need to use a condenser. Usually only applies to flats and a very few wee terraced houses. If you have to carve your house up - tough!

TRV's -Part L of the bldg regs.

 

[Prof.plumb]

I would just like to ask if chris has done his high efficiency exam if he hasn't then i suggest he does. Back boilers can still be fitted in place of back boilers. FACT.

 

[Paul Barker]

Well I did my energy training 2 years ago, so the rulkes about BBU's weren't decided upon. Can you give me chapter and verse and references so I can update myself.

 

[jdey]

Do you have a weblink? The law seems totally vague on most things.

The Building Regulations Act just seems to specify general requirements (See exact wording at bottom of this post). Most of the details on how to comply with part L of Schedule I of the act are contained in Approved Documents L1, L1A & L1B.

The guidance manual (http://www.odpm.gov.uk/pub/731/GuidetotheCondensingBoilerInstallationAssessmentProcedureforDwellingsPDF1258Kb_id1130731.pdf) which tries to assist in the interpretation of Approved Document L1
suggests that a condensing boiler shouldn't be located in a principal living room but also comes with the proviso that it's only guidance not the law. I

The advice document (http://www.odpm.gov.uk/pub/800/GasandoilcentralheatingboilersAdvicetohouseholdersPDF110Kb_id1130800.pdf) provided by ODPM to householders contains the following information:-

"Do I have to have a
condensing boiler?
No. You should have a condensing boiler
fitted if it is reasonable to do so, but the
law recognises that non-condensing
boilers are acceptable if it would be
too difficult to install a condensing
boiler in your home. Your installer will
tell you whether your circumstances
are too difficult."

I'm not sure as to what is deemed too difficult. It seems to me that turning my house in to a bombsite would meet this.

The Building Regulations Act Part L (http://www.opsi.gov.uk/si/si2000/20002531.htm)

"PART L CONSERVATION OF FUEL AND POWER
L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by: -


(a) limiting the heat loss through the fabric of the building;

(b) controlling the operation of the space heating and hot water systems;

(c) limiting the heat loss from hot water vessels and hot water service pipework;

(d) limiting the heat loss from hot water pipes and hot air ducts used for space heating;

Requirements L1(a), (b), (c) and (d) apply only to -


(a) dwellings;

(b) other buildings whose floor area exceeds 30m2.


(e) installing in buildings artificial lighting systems which are designed and constructed to use no more fuel and power than is reasonable in the circumstances and making reasonable provision for controlling such systems.

Requirement L1(e) applies only within buildings where more than 100m2 of floor area is to be provided with artificial lighting and does not apply within dwellings. "

 

[jdey]

From what I can tell (and until I receive a weblink to the contrary), the Building Regulations and associated Approval Documents only deal with the replacement of an existing boiler with a condensing boiler. They don't mention anything about having to make improvements to the central heating system. e.g. a number of people have told me the Building Regs part L say that TRVs are required on all radiators, there needs to be a seperate room thermostat etc. I can't find anywhere were this is stated as a requirement.

Currently, there's a Domestic Heating Compliance Guide which is due to be published before more regulations come in in April 2006, they may appear in such a guide, but it's yet to be published.

 

[Prof.plumb]

It is found in the high efficiency pack, sent to all installers prior to taking the examination.

 

[Paul Barker]

Maybe when you took it but wasn't decided upon when I took it as I said, so how could it then be in print and how could what was printed then be the regulation today? Things change.

Can't you give a better refernce? date author publication page no., publisher.

 

[jdey]

Just how much steam do these condensing boilers pump out? My existing flue faces out towards the street and is to the left of my front door, about 1.5m from the wall between me and the street. There is a drain the otherside of the bay window and the rain gutter also empties in to that drain. If there's a need for a drainaway then I'm guessing I'd have to wrap some kind of unsightly pipe around the bottom of my bay window to feed in to the drain, if I was to use the existing site.

Looking at the guidelines, I get 640 points for a mid-terrace house. if I move the boiler to the kitchen or bathroom, then I get another 350 points for having to move it's location. Giving me 990 points (10 points short of not needing a condensing boiler) In the Kitchen, I'd need to remove 2 kitchen units and pipe up to the floor above. In the bathroom, the simplest procedure would be to remove the hot water boiler and replace it with a combi boiler. In both cases, I'd have an uncarpeted gap left in my living room which would require a complete recarpeting or the fitting of a unit to hide a gap.

Surely, in this scenario, I should be excluded from requiring a condensing boiler and be allowed to put in a high efficiency non-condensing boiler in place of my current one?

P.S. My boiler seems to leak water when I first switch on, and the main burner fires. Over time, the drips get less as the boiler warms up and then stops completely. I'm guessing, it's because the boiler gets so warm that the water evaporates before leaking. Heat exchanger?