Central heating radiator problem.

[johnthemon]

Goodday experts
Two of the radiators in my gas fired (Worcester Bosch 28Cdi combi boiler) C/heating have suddenly refused to heat up. The other five are fine. Checked for air but none to bleed. Tried turning all off except the one in the hall which has no TRV, and then opening the cold ones while leaving the working ones off. Still no joy. I understand there may be problems with "stuck pins"in the radiator valves, which means removing and hitting the pin to rectify, However, the TRV's are tightly fixed to the piping so I didn't know how to remove them and don't want to apply too much pressure without knowing what I am supposed to be doing (I am not a great diyer and am concerned I might bugger up the valves or the pipes/joints and upset the wife by flooding the house). Can anyone offer simple instructions on what I can do please. In case it helps, the valves are listed as TV1A 15mm Angle British Gas. Sorry to be so wordy but hope the description might help those in the know. Thanks.

 

[twgas]

the circled knurled ring should come undone to expose the pin,

 

[D_Hailsham]

You only have to remove the head - not the complete valve. It is normally attached to the metal body by a chrome knurled nut immediately under the head.

Turn the TRV to max setting.
Turn the nut anticlockwise as you look down on the head; use a wrench etc if necessary.

If you can't get the head off or it's different to the above, post a pic of the valve.

NEVER hit the pin with a hammer - it will probably bend it.

Check the pin moves by pressing on it with something suitable; it should go down and pop up when you release it.

If the pin doesn't move, give the side of the valve some taps with a hammer. You can be quite forceful but don't overdo it.

You can also try lubricating the pin with a little silicon lubricant .