radiators,central heating - Plumbing Forum | Plumbers Forums

ste b · 29-11-2008

Good eve peeps,my bro in law, says his radiators are cold but he has hot water,i got my thories but would be grateful of anyone who has any ideas, he changed the pump on the bolier,its not a combi system,he says he bled them all,early days yet i going tommz to have a look,i got a feeling its the trvs, but why all of them together? keeps popping up,was just one radiator last week,now its all of um,lol, i keep you informed, any ideas?

Cheers........

tipper · 01-12-2008

Are there any motorised valves in the pipework that direct the water either around the heating system or to the HW cylinder? Either one 3-way or two 2-way?

If so then the motorised head to the valve may have failed. If so change the whole motor head unit which you can get from a heating spares/plumbers merchant. Can be done without draining down if the valve is a later type.

Some valves can be manually moved with a lever so you can get heating/hw in an emergency.

(It is possible to change the little motor within the head on some makes but frankly the valve mechanism and aux. switch contacts are usually shot by the time the motor fails so change the whole head, it's easier anyway. Shouldn't need to change the valve+motorhead unless it's very old as early ones can't be split)

Mike Jackson · 01-12-2008

I'm assuming it's a system boiler if it has an integral pump but not a combi. After the radiators were bled was the system pressure topped up? As the pressure drops off an a sealed system you will quite often find that radiators stop to work one at a time.

Mike