I have a combi boiler and yet a back boiler too

plantain

I definitely have a combi boiler that heats the house, I also definitely have a back boiler as it sticks out a bit from the chimney breast. I'm not entirely sure but I think the back boiler switches on when the heating comes on as I can hear it, I just can't think why. I do have an old looking fire in the chimney breast.

What I need to know is what type of job is likely to be needed to be done to remove it? will it be still connected to gas and water? any electricity? any idea on costs?

phill99

You will probably find that your 'combi boiler' is a water only heater and has nothing to do with the central heating and the back boiler only heats the rads.

SailorSam

I imagine the Combi will heat both water & radiators. The back boiler has probably been there years unused since the Combi was fitted.
I don't think it'll be a big job to take out, even if it's still connected to the water. That can be easily capped off.

plantain

what could the noise be that i hear coming from the back boiler when the heatings on? could it just be water flow or could it be electrical power?

SailorSam

I don't think there'll be anything connected to the electric or the gas. It's more likely that there are still water pipes there. I think once the Combi fire up and pumps water around the system the pipes behind the fire are getting water pumped through. If it is like that it will be simple to cap the pipe off. I suppose you could take all the old pies out if they don't do anything.
Haven't a clue on cost but to pull out and cap out should only take a couple of hours.

plantain

nice one cheers

rustyboy21

What make are the 2 boilers? If you give us them, there are guys on here like SouthcoastRGI, who can advise you better.


But it could be exactly like Phill99 says. Does the 'Combi' have a name on it like Main medway or similar? If so, that would be a purely hot water heater.

plantain

yeh the boiler says main combi 30 he, no idea on the back boiler, it's hidden behind the chimney breast.

does that mean the back boiler is still heating the radiators?

JustinR1979

Have you never looked for a flame, or heard it sparking?

plantain

the flame will be hidden, one of the lights on the panel has a flame symbol though. also in the user guide it says serves central heating and mains fed domestic hot water. doesnt say anything about a back boiler.

rustyboy21

I am not that fantastically technical, when it comes to boilers, but I think it could be possible, that when the Combi was fitted, they didn't totally disconnect the BBU from the system. They mat have set it up on a type of loop system, for the fire ( which they didn't really need to do, as the fire will work without the boiler being connected)


You could try switching the Combi off and then trying to get hot water or CH working. This would then give you a definitive answer , if the BBU is doing anything at all and then could take it from there. Though I cannot see why anyone would fit both Boilers up to the same system, even if it was possible. Totally weird set up.