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I have a Lennox G12Q3E-82-6
This morning there was no heat. Put new batteries in the thermostat just in case, played around with that. The blower fan will turn on if the thermostat is turned to manual on but not the burner.
There is 120v power going to the furnace and I assume there is gas because the separate natural has water heater is working fine. I tested 26-27 volts at the transformer in the furnace. I hear a click in the tstat when it calls for heat but there is zero activity at the furnace. No clicking, igniter, gas sounds, etc. I checked and re-seated wiring connectors inside the unit with no change. Any ideas? Thank you