Single Radiator stone cold

ChrisBint

There is a small radiator in the en-suite that is stone cold, where all others are working perfectly. I have open and closed the valves and they appear to turn as freely as expected. A thermostatic valve was fitted and this was removed, I also gave the top of this valve a few whacks. Radiator is fully bled, no air is escaping although the pressure might be a little lower than others.

I was going to replace the valves when I have the system drained as I am replacing another radiator.

Aside from this, any other suggestions before I start smashing tiles up to make sure the piping is all present and correct. If anything, I would expect this to get hot quick due to it's vicinity to the boiler itself, but guess it could be at the end of the flow.

Thanks

firefox1956

System could need balancing.......
Read up about it on the internet.
HTH

Mr.Generous

I've found sometimes opening the bleed valve on the cold rad while the system is on and pump running gets the system flowing again. You might have to alternate which valve you open by closing one side with the other open and swapping them over, as soon as water escapes you should feel the feed pipe (usually on he TRV side) heat up. As the hot water enters the rad and rises it may well start it flowing again. Valves can fail, especially TRV's - take the top off and push the pin down, it should spring back up.

Balancing is basically turning down other rads slightly (start with the one's that heat up quickest) to put more pressure on the cold rad.

I have also fixed a single rad like this by turning the pump to 3 when it was set on 2.

Start with the easy ones.

ariba10

When the C H is on turn all the working radiators off and see if the cold one warms up.

Sometimes a cold Rad is caused by an air lock.

Grenage

Is the feed pipe getting warm? It could be an air lock.