Take my TRV apart

[wedge69]

Background:

All bar one radiators in our house have TRVs. Tested the heating was working and all radiators got hot. One weekend I wanted to dry some washing upstairs, so I turned the heating on, but closed all TRVs downstairs.

Now the main radiator in the lounge does not get hot (though the pipe to the TRV hears up a little).

Reading the FAQ, this leads me to believe that the pin may be stuck in the TRV, so I want to take it apart and have a look. However, I can not see how to take the top off the valve.

Can someone tell me how to get the top off? It is a Myson TRV, with pictures below (sorry about the quality). Or, if these symptons do not suggest a TRV problem what else could it be?

Also, if I take the top off the TRV, no water is going to come out, is it?

Cheers

 

[sime10]

could be a trv fault
And no, no water will come out.
Just undew the nut on the base of the head not the pipes

 

[wedge69]

What, the nut circled below? I just assumed that unscrewing that one would cause a leak because it looks close to the pipe....

Cheers

 

[sime10]

yes that nut is ok

 

[sm1thson]

thats the one! -just dont do the other 2!