Back boilers!

[David]

Hi all I looked at a property today which I'm thinking of buying, and was very curious about its central heating system, since it has a back boiler. I know nothing about these things and would welcome the group's views/advice. I think it probably works; owner wasn't there and surpisingly (?!) the agent didn't have a clue.

I thought back-boilers derived from my granny's days, when you had an open fire going all day, and tapped off heat from that to provide HW and central heating. However, this house is 1970's built; has a monstrosity of a gas fire in the living room fireplace behind which, we're told, is this gas boiler. One of those ubiquitous 2-channel clockwork Danross timers sits by the mantlepiece, so sounds plausible!

Upstairs there's a normal airing cupboard featuring a regular copper HW cylinder.

So what's the deal with these gadgets? Will it need replacing? Does it only work when the living room gas fire is on or something? (surely not!) If not why bury it behind the fireplace?

Thanks David

[Nick Read]

They are basically just an open-flued gas boiler that happens to be fitted into the back of a gas fire. They operate independently of each other, so you don't have to have the gas fire on to use the central heating (and vice-versa).

There's no reason why it will necessarily have to be replaced if it works ok, but its probably advisable to have it serviced - like any open flued gas appliance a blocked flu will mean fumes coming out into the room. They also need a good supply of air so you may have an airbrick in the room which must be free from obstructions. Being an elderly boiler it may not be very fuel efficient, but will probably have mechanical simplicity on its side so there's not much to go wrong with it.

Nick

[John Chapman]

They also

I remember some friends of ours had a Baxi back boiler which were all the rage in their new house in the 70s. The boiler had a good reputation and worked well but I was slightly bothered by the fact that you could sit in their lounge with the gas fire off yet still hear gas being burned by the boiler behind the gas fire. When I hear gas being burned but can see no flame then I imagine I am about to be overcome by some ghastly fumes. I also did not reckon it would be easy to service as it was all tucked away. John Chapman

[mike ring]

[e-mail] (David) wrote in news: [e-mail]:

You'rre right, but the modern back boilers can save space, I don't know where in my hovel I'd put another type - maybe in the loft.

They are nowadays fully pumped, and I've found them very reliable (for more than 30 years)

Servicing is usually just cleaning, and they are not all that bad, the firefont and back burner can usually be extricated, and they are simple.

IMO the worst feature is hearing them, especially if they're short cycling, but I've reduced the power on mine and it's now nearly inaudible

mike r

[mike ring]

[e-mail] (David) wrote in news: [e-mail]:

It will be a normal fireplace - (I'm pretty sure, but wouldn't swear to it in blood), which is why the firefront is so protuberant.

Baxi now do a slim profile boiler that will accommodate a fire that looks built in, or a normal firefront only.

Baxi only started making separate boilers and firefronts in the (guessing) mid seventies, check the model with them; the later ones allow a new front or boiler to be installed without affecting the other

mike r

[Owain]

"John Chapman" wrote | I also did not reckon it would be easy to service as it was all | tucked away.

The outer front is only held on to the wall with a couple of screws and lifts off, then the fire lifts off, and then you're left with a lump of cast iron with a flamey thing underneath, which constitutes the boiler. Well, that's mine.

Owain

[Dave Liquorice]

How old is the house? If it was also built in the 70's it may well have been built without a proper fire place just a hole and flue for the back boiler.

Having said that the boiler takes up so much space that there isn't going to be any grate left anyway even if one was orginally there.

I take it you are thinking of removing this gas fire/back boiler and putting a real fireplace in the space? You probably stand more chance of getting a grate back in if there was one orginally but I wouldn't rule it out if not. The flue would need checking for suitabilty as well.

[Martin Angove]

Mum and dad have a Baxi back boiler system in their 1966(ish) built house. Of course it may have been a retrofit since I know for a fact that central heating was an "optional extra" in these houses, but we moved in in early 1973 and it was definitely there then, though the upstairs radiators were only added three or four years ago. In the 1980s it had a new fire front and a new burner in the boiler IIRC, but little else.

The programmer has never worked, and now that I'm moving back down (will be about 1 mile from them) that's something I may play with, though a lot of others on the estate seem to have ditched the things and installed fanned-flue boilers in kitchens, bathrooms, lofts and so on.

The house we're taking on also has a back boiler and our surveyor reckons it is gravity circulated... hmmm... the radiators are new, but the similarly new tank is in a cupboard in the main bedroom (almost directly above the boiler) and with insulation is too big to let the door shut! Methinks that when finances allow something will have to be done about that.

Hwyl!

M.

[IMM]

They drag air from living room and are noisy. Keep it for know and replace wit a nice condensing boiler when you have some dosh.

[Ed Sirett]

Whilst disagreeing with the actual figure of 40% (more like 30% as the best saving in IME). Gas used is the recipriocal of efficiency. A really poor boiler might have an efficiency of only 50% and the best condensing might be 85%. So the old boiler would need 200 units of gas to do what the new one can do with 118. =

200-118/ 200 approx 41% reduction in gas consumption. =

[IMM]

Part L mean nothing below 78%. "Existing" backboilers will be far less than

78%