I have a York TG9S080B12MP11A up-flow configured natural gas furnace. We have had the furnace since 2007. I am having an issue where the furnace is not starting correctly.
- When I power up the blower motor starts up
- If I activate the thermostat (I'm using Nest) the indicator light will blink 3 orange pulses.
Now if I turn off the thermostat, unplug one of the cross connectors between the two pressure switches, turn on the thermostat. The fan turns on, and if I reconnect the cross connector the furnace will sit for about 5 seconds with the blower and the fan running. Then the igniters will start to glow and then the gas will kick on.
The furnace will then run until it comes to temperature and then the furnace will shut down but the blower will stay on.
Last year I replaced the switches, the control board. Last week I replaced the condensate pan (original clear model had cracks in it), the blower motor, put in new switches.