Problem with Danfoss radiator valve

[boilersuit]

One of the radiators in my house has stopped heating up. It was working fine until last week; now it doesn't heat up regardless of the setting on the Danfoss thermostatic valve. The inlet pipe gets warm but that's all. I am assuming that the valve is stuck in the 'closed' position. How can I remove and examine the valve? I can't see any way to get it off the radiator. Any help appreciated! Thanks for reading.

 

[namsag]

Picture would help but if there are no obvious screws try twisting the ring at botto of valve body or give the valve body a few sharp taps to try and free the pin

 

[boilersuit]

Thanks namsag. After mucho fiddling I found a sort of peg thing in the lower black ring of the valve head. When this was prised out I was able to twist the ring and pull the valve head off the rad to reveal the pin. The pin was not seized and when I pulled it out water spurted from the valve, so I popped it back in again. But still no hot water flowing into the rad. So I guess the mechanism inside must be seized? Anything I can do about this that doesn't involve draining down?

 

[kirkgas]

check the other valve has not been closed which would stop the flow

 

[Whitespirit66]

Depending on which Danfoss TRVs you have, new glands (the bit with the pin fits in) are available from Heatingcontrolsonline.co.uk. They can be fitted without draining down.

http://www.heatingcontrolsonline.co.uk/danfoss-randall-rav-ravl-replacement-gland-p-381.html

 

[boilersuit]

Thank you for your suggestions. I just need to find out what model TRV I am dealing with – can't see anything on the body except the word 'Danfoss'.

 

[Dan Robinson]

Post a picture....

 

[boilersuit]

OK, here's a photo of the offending valve...

//www.diynot.com/network/boilersuit/albums/2182/8328

 

[Dan Robinson]

Standby one...

 

[Dan Robinson]

Untitled

• Dan Robinson
• 8 Feb 2009
• 1

Twist that and the head comes off.

Give the pin a smack (carefully).

Refit the head.

 

[boilersuit]

A big thank you to all those who chipped in on this one. The radiator now appears to be working normally again – and not a moment too soon in the current weather conditions!

 

[MarkRainbow]

I can't get one of these valve heads off.... Any tips for stubborn ones?

The black plastic ring at the base only tuns about 45 degrees, tried encouraging it with my pump pliers... next step seems to be break it off