Central Heating Problems: Radiators
CURING RADIATOR PROBLEMS
Cure this by bleeding the radiators every so often using a special key. Fit the key in the valve, hold a cloth underneath, and turn anticlockwise. Close as water appears.
Thermostatic valves (TRVs)
Unscrew and lift off the cover. Underneath is a pin, connected to the plastic diaphragm which opens and closes the valve. Move the pin up and down a few times with a pair of pliers to release the mechanism.
If one radiator refuses to warm up, unscrew the valve cover, then use an adjustable spanner to turn the head anticlockwise half a turn and see if this helps. Repeat if necessary, but only once.