honeywell furnace control board

The ST9120U1011 monitors the thermostat for heat, cool and fan demands, runs the induced draft blower motor and runs the circulating fan (up to two speeds) as needed.

Honeywell S9200U1000 Universal Integrated Furnace Control Circuit Board.

ST9103A integrates control of burner and circulating fan operations in an oil furnace. Features Central appliance wiring point simplifies appliance assembly and service.