Cold Radiator

[kazzawazzawoo]

I have one cold radiator. On reading previous forums, I have removed the plastic cap and "tapped" the pin and hey presto, one hot radiator. However, when replacing the plastic cap, it goes cold again.
Help please

 

[Jamiejohnston]

Is the cap one which needs screwing on? is it a TRV?

 

[kazzawazzawoo]

yes its a TRV.... I think I've unscrewed it and removed the plastic cap & the radiator instantly heats, but within about half an hour of replacing it it goes cold again.
Not sure if it helps but it's a Caleffi.

 

[Jamiejohnston]

Sounds like your putting the wrong cap on it you need to put a trv on it if so. sounds like the cap is closing the pin. search trv on google.

 

[Jamiejohnston]

have you got the plastic cap if so put it back on and make sure the trv is open before screwing if back on.

 

[kazzawazzawoo]

the plastic cap is whats always been on.. worked up until a few days ago....i'm wondering if i'm not quite putting it back on correctly.....i've tried several different ways Just trying to save paying out for a plumber.....
Thanks for your help by the way [/img][/url]

 

[Jamiejohnston]

make the lockshield on the return is open to

 

[Jamiejohnston]

best bet is to take a picture and i can see what it looks like.

 

[kazzawazzawoo]

I've added an image of the thermostat control head....not sure if it will show, it maybe clear I'm new to all this !
there is another connection the other end, which I'm guessing is the lockshield you mentioned? I've left the cap off for now & radiator is red hot ......
[/img]

 

[GasSafeTony]

Does the rad constantly stay warm whilt the cap is off?

 

[kazzawazzawoo]

yes it does, it goes cold when replacing the cap.

 

[cantaloup63]

Take the cap off and turn it over. Check that the pushbutton (that will move the pin up and down) moves as you turn through the dial settings.

You won't damage anything by leaving the TRV head off entirely, it'll just mean that the radiator is permanently on while the heating is on.

 

[Jamiejohnston]

The plastic bit goes inside trv and should them screw on

 

[kazzawazzawoo]

it doesn't seem to be moving... so I'm guessing I need a new cap??

 

[cantaloup63]

it doesn't seem to be moving... so I'm guessing I need a new cap??

Try pushing it. Could be it needs a bit of a "reminder" that it needs to move

If it does need replacing, I'd leave it off for a while since you may well have to replace the whole thing which means plumber time. Or, if there's a radiator somewhere which has a similar valve head and which it doesn't matter so much if it's permanently on or off then you can swap the heads over.