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hello, is there a blinking light on the circuit board in furnace?
if no blinking light then the furnace does not have power...breaker, fuse, door switch etc. Do you have a test meter?
great so red light is on solid?
Thank you. Your thermostat is bad.
remove top section of thermostat to where you see wiring..take wire from R and wire from W and twist together. If furnace starts..then you need to replace the thermostat
so R to W did nothing?
Then you must have a water safety switch or wire open....trace red wire from furnace circuit board R and tell me if it goes straight to thermostat
ok you alright with removing doors from furnace and taping the bottom dor safety switch down?
then with power on...and red lit solid on circuit board....locate R and W again but this time on the circuit board where the thermostat wires attach.
Use a short wire or paperclip shaped in a U...hold one end on R while holding other end on W...tell me if furnace starts
great so R to W started fan ....did light stay solid?
ok now we are getting close....it will blink a 2 digit number...short blinks then long
short...long.long = 12 for example
great...now attach the little jumper right into the terminals r and w instead of holding it...then that 12 code should run 90 seconds...then tell me what next code is or if furnace starts
so furnace did run 90 seconds..did not fire up..and shut down..and if shut down what was that code
I am sorry but must go offline for a while. I am giving you the manual with troubleshooting in the back. I will opt over to another tech while I am gone
Are you ready to start again?