I have a problem with my trv on my radiator, a while back it wasnt heating up so I took the TRV off and pushed the pin and the radiator started working again.  But when I put the TRV back on the radiator it goes cold and wont heat up, this includes the pipe that leads to the TRV but as soon as its taken off it heats up straight away. So for now im having to leave it off so I can at least have a warm room.  Can anyone help? thanks

Sounds to me like the valve / pin may be sticking. Try working the pin back and forth a few times to make sure its free

Hello ellmit as per you description of your problem with your home radiator and its TRV,I think your TRV must be faulty, how much was it? some cheap models have a tendency to fail. Could you try taking the head off and getting it replaced? It sounds like the pin moves if it allows water through when the head is removed so maybe the head is not working to adjust the pin?