Radiator not working

Ballyman

Hi

I have one rad thats luke warm instead of hot like the others. I'm not sure if it's the first or last rad on the line. It's in the room close to the boiler so it may be either.

I've bled it and it's still lukewarm. I turned off all the other rads and it then heated up properly. When I turned on the other rads again it stayed hot for about a week but it's back to luke warm again now.

Anyone have any idea what might be causing this? Does it need to be balanced? How do I do this?
Is it some other problem maybe? I thought it might be sludge but the fact it heated up when the others were off I presumed it wasnt.

Any help appreciated.

Cheers

DoneDL

Best done with rad thermometer, but if you slightly close the the valves on the return of the hottest radiators until the problem rad is hot then that should do it. The return is normally the left valve but always the cooler of the two pipes to the rad, if there are trvs fitted its the other one.

Ballyman

Cheers. I'll give that a go.

garlad

Sorry to hijack, but am having similar problems.
Had the kids helping me at the weekend to try to figure out which rads heat first etc.
Noticed that on one or two rads, the return pipe would heat faster than the on/off pipe would (if at all). Does this just mean that at some stage the plastic knobs were put on the wrong sides?

DoneDL

Radiator valves were once one way only which meant that they had to be valved specifically to flow and return, new valves are bi-directional so it doesn't really matter but if trvs are fitted its best to have them on the flow as it makes balancing a system easier. If the valves are wheel head just balance the system and put the lock-shield ie the valve head which doesn't turn on the return.

garlad

My rad valves are these types:



Its a fairly old system I reckon.
Should I assume the colder pipe or the one which heats second is the return, and balance using that valve? Then fit the appropriate plastic head.

DoneDL

Yes thats it