Symtoms	Possible Faults
No DHW	Check dhw microswitch
No C/H	Check dhw microswitch if dhw demand led is lit
No C/H but boiler is firing	Check divertor motor and cartridge
Boiler locks out within 10 seconds	Check pump proving switch, air pressure switch and overheat stat
Poor burner pressure	Check burner pressure/ignition adjustment pots on PCB

Key Areas