Radiator

[buildersbutt]

Hi all have a open heating system, the problem is when switching on hot water only the radiator in the bathroom heats up. Have only just noticed it so don't know how long this has been going on. Had a new boiler fitted just before Xmas 2015,all help appreciated, thanks for your time.

 

[stem]

In the past with solid fuel boilers, it was very common to pipe up the bathroom radiator to the hot water system. Sometimes this arrangement would be left in place when the boiler was replaced. However, if that were true in your case, then I would have expected that you would have noticed before now.

There are other causes such as 'Reverse Circulation' where due to incorrect piping, the return flow from the hot water cylinder can pass through one or more radiators, or it may be that a motorised valve (if you have one) is letting by slightly.

If you have an old 'Single Pipe' system, some water may circulate by natural convection even if the heating is off.

Really you would need to provide a bit more information about the layout of your system pipes and what type of installation it is. Does it have motorised valves? Is it fully pumped, or is the hot water system heated by gravity circulation? Does it conform to one the common arrangements i.e. S Plan, Y Plan, C Plan. etc.,