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Hello, set the fan switch on the thermostat and tell me if the fan comes on or not.... if not, check for a blown 3 amp fuse on the printed circuit card, its an automotive type.
To go much further you will need a multi meter so we can check fo 24volts ac at the furnace transformer or 19volts from the red wire that runs to the thermostat to the bare metal threads on the gas piping.
Hello, since the fan runs, that proves the transformer and fuse are good we do not need the multi meter as badly.... we can still use voltage reads on other issues that remain to be seen as we go along however.
Next send me a close up photo of the wiring diagram glued to the inside of the blower access panel on the furnace, photo must be well lit, and *exceedingly well focused...I will mark it up with trouble shooting instructions.
So far it looks like a tripped high limit or door switch if we are lucky, or a bad printed circuit card if we are not as lucky.
Thanks, ***** ***** unplug the furnace, and disconnect the wires from any limit switch or flame roll out switch you want to test then use your ohm meter to see if its open or if the contacts are closed as they should be.
Yes the circuit board.
You cannot tell if a switch is tripped by looking at it... you must disconnect it and use a multi meter set on ohms to determine if it is tripped or not.
The training required to sort these things out is 2 years of community college HVAC labs then a few years in the field working under a journeyman... I can coach people with a base of skills with a multi meter, but if that is not the case we can waste a lot of each others time.
At this point if you can tell me what direction you are from the center of the nearest city I will look for a well rated outfit that can arrive and do the diagnosis and repair for you.
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