could be the radiator is full of gunk? if its a little bit warm this is most likely the case,try turning all ur radiators off except the one in the bedroom and leave it for about 15mins and if you get heat then balance all the rads out until there all banging heat out.if not it sounds like the trv has failed just replace the trv(and give the radiator a flush out while its off) they dont cost that much.if that doesnt solve it,it could be something to do with the flow supply
plumber grant
December 2009
check supply pipes coming to the radiator open the lockshield on the hottest pipe (this should be the supply side) open the bleed screw and listen for HISSING when water appears close bleed valve now check the radiator for HOTNESS
another possibility if a TRV fitted, the little plunger in the head can stick down if the valve was totally turned off, no problem remove the TRV head and now give the metal body a gentle tap till the little pin pops up(rad will now heat up) work the pin a few times then refit the head. never turn he TRV past the * setting
wirecutterman
December 2009
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