The Central heating boiler fires up and the pump runs, but the flame cuts out before the last radiator in the loop has had time to get warm. The pump keeps going. The boiler fires up again after a while and then cuts out again a few minutes later - this sequence repeats. It is not the room thermostat control turning it off. I have bled the radiators but this made no diference. What else can I try.
seems the boiler is cutting out &in again on it's overheat thermostat, if your pump has 3speeds move lever to pos. 3 ie move more water through boiler, or try turning boiler control down a little,
the setting limits the ultimate rad temp so will seem cooler but room will still get up to temp. even if a little bit slower.
if an old system may need flushing & new rust inhibiter adding,