Upstairs radiator. It's not even warm. Turned on after a year or so of the room not being in use. Have tried bleeding, but only water comes out, no air. Pipes leading up along the wall to adjacent room are hot and radiator in adjacent room works, but even the pipe below the TRV on the problem radiator is icy cold. Any ideas?
Marcus
Crud under the lockshield valve? Open the lockshield (count how many turns), open the TRV all the way (set to max temp) and run it for a bit. If that moves the crud, then put the lockshield back where it was. If it doesn't, put it back anyway!
(especially if the LSV is actually not open very far to start with)
I see you didn't mention checking for a stuck pin in the TRV. Do that first, of course.
In message , Marcus Fox writes
The brass pin in the TRV has stuck
Place a spanner on it and tap it gently with a 'ammer - it should release
It can be a stuck valve pin or crud in a valve as has been suggested. It can also be an airlock in one of the pipes. Particularly if this is a small radiator with low flow, that can happen. Bleeding with water coming out as you have, still happens because water enters the radiator via the pipe without the airlock.
There are two ways to check for and fix this:
- Close the lockshield valve after marking its position. Bleed again. If water and some air comes out, you will have found and cleared the problem. If water and no air then it wasn't this pipe. If nothing, then either there is air in the pipe, or the TRV is stuck. Repeat with lockshield open and TRV closed.
- If crudded valves/stuck TRV have been eliminated and it appears to be an airlock, then close the TRVs on all other radiators, open them on this one and wind up the pump speed to max. This should remove air lock bubbles.
Beyond that, there could be a blockage in the pipe but that is getting less likely and at that point it would be a case of shutting off the radiator and removing it and flushing out at the radiator position. A messier procedure.
Unscrewed the TRV cap and the radiator came on. Fitted it back, now it seems to be working OK.
Thanks guys
Marcus
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