Call for Heat (Thermostat + Programmer)
Fan Runs
Pressure Switch detects fan running - tells PCB
PCB opens pilot gas valve and makes spark
Pilot lights (automatically)
PCB senses heat from pilot light and opens main gas valve
Main Burner lights...
Peccavi
December 2008
I can answer this question...
How do I light my Pilot Light for my potterton Profile Boiler?