radiators

[val-sis]

Does anyone know why a radiator doesn't get hot, when all the rest in the house are fine. I have tried 'bleeding' it but that is not the answer, as the water comes out when I do.The pipes leading to the rad, are hot !!!

[ianmunt]

All to do with balancing the system.The flow is taking the easiest path.Its a case of gradually reducing the flow to other radiators,by adjusting the return side valve(It will have a cap on which doesnt turn the valve) Temporarily remove this and using the valve top ftom the other side of the radiator turn the valve clockwise to reduce the flow.You should do it a little at a time,and I'd start by adjusting ahe hottest radiator first.

[chas2008]

although systems should be balanced and its amazing how many are not it could be just a bit of sludge/gunk preventing the flow. If you have ever removed one for decorating and ran a hose through it you will know what i mean.
Try closing down all the other rads this will then give increased flow to the rad in question and hopefully clear it.
(i assume you have checked to make sure both valves are open ? )

[val-sis]

Thanks Ianmunt, but am not really sure what you mean...I have a thermostat (marked 1 - 5) on the R.H side..do you mean the L.H. side to be removed? cos I've tried to lift it off & it won't budge. Sorry to be so thick.

[val-sis]

Thanks chas2008, have now done this, and am waiting for a result. Perhaps it takes a bit of time,(did it 10 mins. ago)nothing as yet.

[ianmunt]

generally a thermostatic valve is on the flow,or input side.the other side(left in the case you describe will be the return side) Without removing the cover you cannot adjust it.Since you have thermostatic valves you will need an adjustable spanner or mole grip to turn it, rather than the valve cap.However,if you have any radiator without a thermostatic valve (and there should be one) then it will have a suitable cap which will do the job.
But try Chas2008 approach first and see what that does.

[chas2008]

not uncommon for TRVs (thermostastic valve) to stick

http://www.diynot.com/forums/viewtopic.php?t=8 8367

[chas2008]

its also not uncommon for thermostatic valves to stick

Sticking Thermostatick Radiator Valves (TRV's)Quite often, after the summer when you start to use your heating, TRV's will stick causing radiators not to heat up. This is quite a simple job to fix; first, remove the TRV head from the body. Once done, you will see a pin in the middle of the body - it is this that sticks. Hold the tip of the pin with a pair of small pliars and push and pull it up and down a few times. This can free up the pin and allow the TRV to operate correctly again.

[val-sis]

Ahhhh! Thanks to you both, Good grief ,its all so complicated for a novice!!! I only had the new boiler put in (and all the thermostat valves etc.) in September, and it seems to have worked fine until the last couple of days...things always happen at Christmas eh....cheers guys, will certainly go for all your advice.

[tezestwing]

val It is inevitable that a problem occurs in the first few weeks, it is quite a major op to the system, I would have a friendly chat with the installer they should come back and sort things like this out good for business hth Tez

[tezestwing]

foc of course Tez

[W.LOVELL]

get yourself a radiator key, with heating on, find the small bleed screw & turn gently until a hissing sound is heard, when it stops tighten the screw. you should feel radiator getting hotter.

[tabytha]

i have exactly the same problem in my house but im renting trying to get them to sort it out is impossible! if the rad is on in my bedroom my sons is off and if mine is off his is on why lol??

[sddsddean]

At least one of my TRV's stick every year. I give it a VERY gentle tap with a small hammer and the pin pops up...problem solved.

[gucciman]

you never vent a radiator with the system running as you can suck air in.

firstly make sure the none trv valve is fully open then unscrew the head of the trv, if the radiator then gets hot its the trv head at fault, if the radiator still doesnt get hot then it's the trv body at fault. as said before try pulling and pushing the little pin aong with a bit of grease or wd40, and gently rap the side of the valve with a spanner or small hammer see if that frees it up.

if it is the head at fault then buy a new valve of the same type and just replace the head.