Burner not always lighting?

if the pump is ok then ive had a problem where the boiler has to be turned on and off at the mains power supply because the air pressure switch stays constantly stuck in a made contact position and doesnt drop to the open position automatically when the boiler is satisfied so turning it on and off at the mains manually did what should have been an automatic process. there is a more scientific way to prove this with a multimeter, which i cant fully remember

john
January 2010

if the pump is ok then ive had a problem where the boiler has to be turned on and off at the mains power supply because the air pressure switch stays constantly stuck in a made contact position and doesnt drop to the open position automatically when the boiler is satisfied so turning it on and off at the mains manually did what should have been an automatic process. there is a more scientific way to prove this with a multimeter, which i cant fully remember

john
January 2010

you may have a sticking relay on the circuit board preventing the boiler from igniting until it's re-set. as for the overheating, first thing to check is that the pump is circulating correctly.

Ian
January 2010