One radiator doesn't get as hot as the others

Igotadose

in one room, we have a lot of problems with not enough radiator to warm the room. In addition, the one radiator in that room, doesn't get as hot to the touch as the rest of the similarly sized ones in the house.

If I close the valve on all the working radiators and bleed the radiator in an adjoining room, which I suspect is the last one before the heater, *then* the underperforming radiator will heat as well as the rest. But, this lasts for a few days, and the process repeats.

I suspect "something" is allowing air into the system. Bleeding radiators every other day gets old; should I consider replacing the 'bad' radiator? I'm not sure it is the source of the air infiltration - it's not like there's leaks around it nor do I hear any hissing sounds. When there's air in it, I do hear gurgling from it and especially the 'downstream' one that I end up bleeding.

Is there a valve that can be installed at the boiler, to let the air out? Or on the bad radiator?

Thanks

Cantona's Collars

Just want to bump this as I'm having trouble with one rad,all the rest are piping hot but the final rad in an extension only gets hot in the top quarter of said rad.The pipe with the trv fitted is hot but the other side remains cool to the touch.I opened that valve fully but no result and closed it back slightly.
This would be the last rad in the circuit through the house and is downstairs,my multifuel stove heats the rads with no oil used and I can empty my system where I terminated the original pipework from the now removed oil burner.I opened that today to literally drag the hot water through the rad and flush out any air or residue.Still no improvement in the rad.
Stumped now,so is it time to get a plumber in?

exaisle

Sounds like the rads aren't balanced. Have a look here:
http://www.lovekin.net/m.radiator-balancing.html

Cantona's Collars

exaisle wrote: »

Sounds like the rads aren't balanced. Have a look here:
http://www.lovekin.net/m.radiator-balancing.html

Went through them all,checked they were balanced before.I'll go through them again tomorrow.My other option is closing down all the other rads and forcing the hot water through the rad to see if there's a blockage at that valve.By right,it should be hot to the touch but is only room temperature.

Cantona's Collars

Feck all heat in the problem rad yesterday, I was away and came home to the others being piping hot and this one almost cold.I opened off the valve on it and should have been greeted by a leak at least but no water at all. The pipe on the side where the TRV is has heat but nothing going through the rad.

Igotadose

If you turn off all the other radiators and open the cold one wide, does it heat? If not and you bleed it, does that improve things?

I found that I had to bleed my cold radiators till they warmed up, with all the other radiators turned off via the TRV. Once no more air came out and the cold radiators were good and hot, I would turn on each other radiator one at a time, verifying no loss of heat in the original cold ones. Seems to have fixed the problem.

Cantona's Collars

I seemed to have pretty much solved the problem-I hope.I took off the TRV and it looks as if the pin was stuck.I opened the other valve fully then and the rad started to heat.