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Hello, one minute while I get some information together.
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What likely happened is the low voltage fuse in the furnace or airhandler blew. There typically is a SLOT STYLE 3-5AMP FUSE on the board itself inside the furnace/airhandler like this.
If that is burned out all power to the thermostat will be lost. 95% of all units use some sort of SLOT FUSE or inline BUS STYLE FUSE to protect the low voltage circuit. You need to find that and change it out. If you just bump two wires together you could have just popped it without even knowing it. Now if for some reason your unit does not use a fuse often the board will be damaged due to the short. You would need to confirm you have 24 volts to the board inside the furnace/airhandler with a volt meter to make sure though.
Note if you have a condensate pump check the float and make sure the pump is not full of water...as that could cut low voltage power to the unit as well if the pump is not working and full of water.
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It should be on the main board you should see it. That S86 control is just the spark ignition control it should be on the other board.
Yes but that is just the ignition controller. You should see another board besides for that one.
Can you get to the transformer to check it for power? Also do you see the wiring diagram on it? If so take a picture of it and upload it here please.
The fan works right?
OK so you either have a limit switch tripped or the vent switch is tripped.
The limit switch should be around the burner and have two wires on it. Check it for continuity.
Yes that is it press the red button in the middle one may be tripped.
Check the other one then they both have to have continuity
Can you jumper the 24V terminal to the TH-W terminal and see if the unit fires up?
There should be
Can you take a picture of the control with wiring and upload it here. There has to be a wire connected to the terminal marked 24V or 24 V ground is there on either?
Put the TH-W wire on the 24 volt terminal also did anyone change any wiring on it?
The wire to the right of the 24 Volt terminal should be on the 24 volt terminal it is not working since you have the Thermostat wire on the wrong terminal it has to be on the 24 volt terminal...did you take wires off at any point before all of this?
Now try it
Let it wait for 5-7 minutes and see if it starts
I am signing off for the night get back to me in the morning.
Did it come on?
Yes sure sounds like it check for 24 volts from the 24 v connections at the board, if you have 24 volts across them the ignition control is bad.
Then you either have a thermostat issue or a transformer issue.
The you have to check power from the thermostat back out to the unit, a wire may be broken or a limit is bad.