SF 42 furnace madness
So, turned on heat and got fan but no ignition. Pulled furnace and cleaned, while also doing a tune-up. New sail switch, new overtemp switch, new ignitor and new burner installed. Bench tested 12v + a...
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It's the OEM Coleman analog t-stat with furnace, fan and AC operations. Built in time delay relay is printed on the cover.
I followed my blue wires from the furnace harness to the on/off switch on the circuit board. Switching their position on the switch, had no effect on the operation of the furnace. Yet still, if I jumper these 2 wires, the furnce blower runs, sail switch closes, gas valve clicks and ignitor sparks. Once I remove the jumper to the blue wires nothing happens. T-stat set to HEAT, and TEMP set to 90* and nothing happens.Only with the jumper in place on the furnace harness can I get the unit to run. On top of this, setting T-stat to Fan/High or Low and/or COOL Fan/High or Low nothing happens. I'm pretty much pulling hairs out of my head!!!
I followed my blue wires from the furnace harness to the on/off switch on the circuit board. Switching their position on the switch, had no effect on the operation of the furnace. Yet still, if I jumper these 2 wires, the furnce blower runs, sail switch closes, gas valve clicks and ignitor sparks. Once I remove the jumper to the blue wires nothing happens. T-stat set to HEAT, and TEMP set to 90* and nothing happens.Only with the jumper in place on the furnace harness can I get the unit to run. On top of this, setting T-stat to Fan/High or Low and/or COOL Fan/High or Low nothing happens. I'm pretty much pulling hairs out of my head!!!
