TRV valve always on full.

[Grahalex]

The TRV valve on one of my radiators, approx 5 years old, is always on, even when it is turned to 0. I have swapped the top part with one from another radiator, and it didn’t make any difference. Can anyone suggest anything to fix it please ?

 

[ShaunCorbs]

Replace the whole valve

 

[Grahalex]

Would the system need to be drained to do this ?

 

[ShaunCorbs]

Would the system need to be drained to do this ?

Yes

 

[Grahalex]

Thanks for your help Shaun.

 

[Best]

Would the system need to be drained to do this ?

On some homes it could be replaced without a full drain down, but only by someone experienced.

 

[Grahalex]

On some homes it could be replaced without a full drain down, but only by someone experienced.

 

[Grahalex]

I will have to get a plumber in and see what he says.

 

[TMHM]

Although the best option is as above, I have had some success with removing the top and pressing down the centre pin in the top of the main body. This gets jammed with the crud in the pipes. Sometimes you can free it up. It works as a temporary repair, but once it has started to jam, its only a matter of time till it does it again.

 

[Best]

Usually the top pin gets jammed because on old TRVs the gland does not fully seal and water constantly escapes and causes corrosion.

 

[Ric2013]

If you get a plumber in, he or she may be able to freeze the pipework instead of draining down, but it won't be any cheaper. Possibly quicker and less hassle though.

 

[Grahalex]

I could give that a go then.