Danfoss thermostatic valve.

[BobScot]

hi all, I hope someone can recognise the valve I’m having a problem with. My son has just moved in to a house and all the radiators are working except one. I tried bleeding it and managed to get some warmth to the valve on one side but there is no heat on the thermostatic valve side. I think the thermostatic valve may be faulty but wondered if I could swap it with one of the other valves throughout the house. The problem is I don’t recognise the type of valve and don’t know how to release the top of the valve or even if I can, I think the valves may be at least 20 years old.

 

[Londoner2]

Pin could be stuck, pretty sure you can pull it out and pull the pin out slowly, just google teh make on youtube to show you how.

Same thing happened to me, i used pliers to slighty pull teh pin out a few millemetres.

 

[ianmcd]

with the valve head set to max undo the screw i have marked and pull the sensor off, you will see a small gland nut , remove this, a tiny amount of water will come out but not a lot , clean the pin with steel wool or emery paper grease and refit , put the sensor on and tighten the screw and you should be good to go

 

[ianmcd]

On inspection with image blown up it looks like the screw is missing so the head should just pull off

 

[BobScot]

Hi, ianmcd, did as you said, no water came out when I removed the gland nut, is this an indicator of something else wrong? Took the pin out, it was pretty gunged up, cleaned it and reassembled, have put heating on again and waiting to see if it worked!

 

[BobScot]

Hi again, ianmcd, just a thought, can I take the sensor head off a working rad and try it on the faulty one or is more likely to just be the pin sticking?

 

[ianmcd]

yes of course you can but it will be the pin sticking, if you think it is the sensor head just leave it off and see if the rad heats up, just make sure the pin is nice and clean a little dab of silicon grease and you should be fine