A reluctant radiator

[adrianxw]

The "boiler" in our house is upstairs. When the weather turned cold again, I switched it from hot water only to heating and hot water. After an hour or so, I circled the house looking for issues, and found one. The radiator in the kitchen was not "hot" like the others. I'd seen this before, and removed the thermo valve with an Allen key, and manipulated the little pin with a pair of pliers - I'd done this several times in previous years on several radiators, normally this quickly resolves the problem. This year it did not. The radiator inlet pipe is slightly warm, I suspect this is thermal conduction through the pipework however. Looking for the "next step".

 

[Ben-gee]

Assuming the lockshield end has not been closed.
Try closing all other rads, so the pump is just pushing through this one. Does it get hot?
If not it is probably time for a new valve.

 

[Timmy D]

Does the rad pipework just feed this rad? I assume from upstairs as you mention the boiler is there. If so, prob air locked.

Close one rad valve and crack the nut on the opposite valve and draw water out into a rubble sack until hot. To the same for opposite side. You’ll likely hear a load of air come out.