Adding radiators to gravity hot water system.

[MickBrown]

A customer of mine has a coal fire with back boiler that gravity feeds a hot water cylinder. The pipes between the two run partially through the kitchen where a small radiator has been added. The house is a dormer bungalow with a bedroom/bathroom conversion in the loft, the F&E tank has been fitted high in the apex of the roof void. The customer wants to know if 2 extra radiators, 1 small 1 medium size, can be fitted in the loft conversion so these rooms would get heat when the fire is lit. A pump would have to be fitted and some sort of control system but in general is this feasible? He told me a plumber, who did the plumbing of the bathroom conversion, said it could not be done. I do not see why not other than the fact that maybe the heat output from the coal fire may not be sufficient.

 

[2011dkm]

Sounds feasible in theory as on a lot of old systems, the bathroom rad is fed from the circs. But these radiators always seem to gather more sludge build up and trapped air for some reason. As you will be the one at the end of the phone to solve any future problems "feasible in Theory" doesnt give much confidence. I would be tempted to advise installation of electric / oil filled rads.

 

[REDSAW]

tell them you can do the job but it may not work well.

 

[Bradleyruss]

The back boiler when supplied would have information to advise on it's maximum capacity output. You need to do the calculations based on room size, window size (if any) radiator sizes for all those already fitted and to be fitted. If these are within the capacity for the boiler, as with any other then it should heat the room. the problem of course is that you don't specify which type of back boiler so it could most likely be cost effective to replace it with a gas combi.

 

[TBServices]

Only coal fire back boiler system I worked on was incredible. Ridiculously hot.

Just need a pump fitting.

 

[AWheating]

it can be done at a guess. best get a hetas engineer in for advise/ to do the work. it will have to meet the building regs etc....

 

[MickBrown]

Thanks for the advice, the boiler is 40 years old so unlikely to have any paperwork left but I will ask. I will check with building control but I think you may only need building control for fitting of the fire and boiler, adding radiators may not need building regs. I will advise that it can be done but depending on the heat output of the boiler will depend on how well they will work.