Cold Radiator

[studlywonder]

Hi guys, I have had a cold radiator in my bedroom for a week or so now all the other rads in the house are roasting hot. I have a closed system combi boiler which seems to have 2 pipes going to either side of the house(bungalow), the first ones going to lounge then to front bedroom and the other going to kitchen - bathroom - back bedroom - master bedroom.

I have been into the loft space to feel pipes and to see at what point they get cold. It seems that they are cold at the back bedroom to master bedroom point which would concur with the lack of heat.

I have already tried turning off all rads apart from the cold one. Turning up the pressure a bit and still nothing. All rads have been bled and there seems to be no air in the system. The bedroom in question does however seem to be the one furthest away in the system so i am assuming that it is pressure related? I hope someone can shed some light on the matter for me!

 

[Softus]

Does the cold rad by any chance have a TRV on it?

 

[studlywonder]

I think that may be what the problem is! I have tried unscrewing it and giving it a tap with a hammer as suggested on other threads. This seems to have done nothing. I had a look at the other working rads and they seem to have the same valve type thing. I assume this is what the problem is and I just need a new TRV. What is involved in doing this? Can i do it myself or should i let someone who knows do it? Is it a big expensive job or a 20 min fix?

 

[Softus]

...new TRV. What is involved in doing this?

1. Stop water entering the F&E.
2. Turn off boiler and pump and prevent them from running until you're ready.
3. Fully drain the system.
4. Put a paint tray under the valve, and disconnect it from the radiator.
5. Empty rad into tray/bucket/sponge/towel/nearest item of absorbent clothing.
6. Remove valve from pipework and fit new one.
7. Make valve on to radiator.
8. Fill the system and vent all rads. Check your joints.
9. Turn on the boiler/pump and test the system.
10. Stand back in amazement.

Can i do it myself or should i let someone who knows do it?

Its up to you. It isn't a very difficult job. Clearly there are pitfalls, but some research on this forum and the wiki will stand you in good stead.

Is it a big expensive job

No.

...or a 20 min fix?

No.