One radiator stone cold and cold pipework

purpleparrotuk

Moved to a new house yesterday and tried the central heating out. Its a early 70s build and the boiler is at least 20 years old (recently serviced though).

None of the radiators heat up very evenly and 1 of the 2 in the lounge doesn't work at all. The pipework to and from it is stone cold. We have checked the valve is open and the thermostat seems to turn ok. Could it just be sludge in the system? I intend to have a new boiler fitted and the heating checked over but was hoping to wait until after christmas.

Shall I just get a plumber out to check it or could it fix it myself?

Alex1983

It will probably be the pin on the trv stuck, what valve is it, try removing the trv head and freeing the pin underneath. The system sounds like it needs balancing.

bertiewhite

I had stuck TRV pins on some of my radiators after last summer so as Alex has said - take the top of the TRV off and GENTLY tap the pin to free it.

It's probably a good idea to try bleeding every radiator as well.

langsmith

bertiewhite wrote: »

I had stuck TRV pins on some of my radiators after last summer so as Alex has said - take the top of the TRV off and GENTLY tap the pin to free it.

It's probably a good idea to try bleeding every radiator as well.

Shut all of the other radiators off, first - it'll help 'find the radiator' first. Once warm/hot, open the other rads again. If the problem moves or continues, they need to be 'balanced'.

Search Google for 'Radiator Balancing'.

Note: the bathroom can be left as is; usually no TRV just valve and lockshield.

DaftyDuck

As in your House Buying thread (:hello::hello:), it should be easily fixed.

It could simply be air-locked (unlikely, if pipes are stone-cold, but possible). Radiator key in valve at top, cloth to hand, loosen gently... air or water coming out? Let all the air out...

It could be you've shut the valve fully,not opened it. The thermal valve should be set as hot as possible (for the moment), the lock valve at the other end may need opening. If you are unsure if the knob is working (they often break), lift it off, and turn the top bit gently, using pliers.

As others have said, it might not get heat because the other radiators may be "stealing" all the flow. The whole system may need balancing. That's something well worth doing yourself, and understanding, as you will end up doing a better (and more personalised) job than a hasty plumber. Try turning the other radiators down using the non-thermal valve, the lock-valve at the other end. By restricting flow to those, there's more "spare" flow for the radiator that's cold.

It could well be the pin on the thermal valve. Rapid turning on and off of the knob (with the system on and hot) may well help. Removing the knob (it won't leak) by the collar at the bottom allows GENTLE tapping of the side, or even the pin itself.

If the valve is well and truly seized, it's still a DIY job to replace it, and not that difficult. But try all the above first.

If it's sludge in the system, it might be difficult to shift, but even that's a job you can do yourself.

Enjoy your new house!