Green light going on and off?

green light is the burner on light if it is going on and off quickly, burner is lighting and then failing. it will do this only 5 times and then lock out (red light, requiring rest) as only happenning in morning, check inlet gas pressure not too low on ignition (gas supply or meter governor sticky) check combustion fan nor worn (too slow on start up check flue or condense drain not frozen. if green light stays on for a while before going out and then keeps relighting after a few minutes then boiler is too quickly reaching temperture going off and refiring when cooler this is a slow circulation fault. check/change boilers pump first as can run too slow 1st thing after nights lay off

deano
November 2010