take cover off burner,the red plastic bit,on l h s of burner is the oil pump,using a spanner just undo but not remove the bottom silver bolt below the slotted screw,don't turn the screw slotted bit this adjust the pump pressure,the bolt you want is below this bit,press lock out button and let burner run with screw loose but not removed,keep finger on button and oil will fizz out of bolt,if it sprays push button in an burner will stop tighten up bolt and rest lock out,boiler should fire,this may take several attemps to clear all the air
simon carter, December 2012