One Cold Radiator

[Plumboutofideas]

Hi New to this site so be gentle with me. I have a problem with a CALEFFI TRV, I have read through the help files on this site and tried to remove the head cover as described but the problem lies in there is no screw at the top and it does not want to come off the fitting. bled some water out and there is no air coming out. So any ideas would be gratefully received.

I have uploaded to pics to show the valve in question.

 

[seco services]

half way down is a knurled nut just above the elbow unscrew that and the head will come off

 

[Plumboutofideas]

half way down is a knurled nut just above the elbow unscrew that and the head will come off

Thank you for the quick response to my query. Forgive me for asking stupid questions but if I unscrew the valve from the knurled nut wont this allow water to escape. Maybe I did not explain fully my intensions, which is to expose the pin so I can press it down to actuate the trv to work again or am I looking at it wrong?

All the other radiators are working fine except this one. It stopped on Tuesday for no reason

Will I have to replace the TRV with a new one and if so, do I need to drain the system.

 

[Slugbabydotcom]

If you undo the nut on the left or the bottom you will get wet! If you undo the 'uppermost silver bit' the head will come off. turn the dial to its highest setting anticlockwise before you remove or refit the head.

Pushing down on the pin actually closes it. Tapping downwards gently on the pin sometimes frees, it as does tapping the valve gently with a spanner or hammer.

Go careful if you plan on pulling at that pin. You may get wet or at least end up with a problem if you totally remove the pin and drop it through a gap in the flooring. Whenever I have accidentally pulled the pin out I have always managed to get it back in but sometimes theres a jet of water coming at you when you fumble about which makes you panic a bit.
If you are a bit mad like me you could scare yourself even more by having the system turned on while you do it I did this once and it turned my slug trail brown

Some modern TRV's are designed so you cant remove or pull at the pin. I'm not familiar with that particular TRV although Caleffi are well known for their pressure relief valves which are fitted to most combi's. Most of us will have probably fitted the same TRV with a different name on it!

 

[Plumboutofideas]

Thanks for the reply Slugbabydotcom

I will have a go at taking the head off and I will let you know the outcome

 

[Plumboutofideas]

That was so easy!!!!!!!

Undid the knurled nut, pushed the pin in a few times and then the radiator went hot straight away, then refitted the TRV, problem solved great. Thank you Seco services and Slugbabydotcom.

this site is certainly helpful and a money saver