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My furnace is not turning on. It has power, and the indicator light has the correct "heartbeat". I can turn the fan on manually with the switch on the thermostat, and it comes on and seems fine???
Hi,I will need you to try some things when you are ready.
I need you to go to the furnace and find the main circuit board. You will find some small gauge wiring connected to a terminal strip that has terminals labeled R, W, C, Y, G. I need you to jump the R terminal and the W terminal together without touching any other terminal. A small wire is appropriate for this. You will need to tape the blower door switch closed to make the unit run, also if the door is off.
I taped the switch, pulled the fuse, and put the jumper wire in. As soon as I put the fuse back in the blower came on.
That is probably the fan cycle power-up. Let it run through the cycle. You jumpered R to W correct?
Yes R to W. My diagnostic light is flashing three times now. The book says 3 = pressure switch open when it should be closed.
Is the small inducer fan operating?
Is that on top? It is not running. The blower is still running.
Ok, was the blower running before?
No. I could turn it on with the switch, but it wasn't running on "auto".
Jumpering between R and W bypasses the thermostat and should bring in the inducer fan. It is the small fan with the vent pipe connected to it. The sequence of operation is as follows: thermostat calls for heat (between R and W) Inducer fan starts, Pressure switch closes, Igniter energized and then trial for ignition.Shut the unit off and remove the rubber tubes from the pressure switch (round, disc shaped device with small tubes connected to it). Blow through the tubes and reconnect them. Turn unit on and see what happens.
No changes. This unit is less than a year old.
Ok so the small inducer fan is not running right?
No it is not. I put a better wire to jump the R and W. The blower fan is not running anymore, and the indicator light is flashing 3 times.
Ok, that indicates a problem with combustion air-flow. The inducer fan needs to be running, Again, is it running?Thanks
No, it is not running.
Ok, That would be the next step. We need to determine if there is power going to the inducer motor. I need to know if the inducer fan motor has failed or something else.
There should be a molex connector that you can disconnect and check voltage when you try to start the furnace. Remember, the inducer fan has to run before anything else can happen.
I have my multi meter now.
Ok, what and where is a molex connector? How many volts should it be?
It is a plastic connector where the motor wires connect to the wires feeding it.
Yes. Do the wires lead to the inducer fan? If so disconnect the plug and check to see if power is going to the two terminals in the plu (not the motor end connections). You will need to shut off the power and get your meter leads on the connections and then turn the power back on. You should see 120 volts (give or take a few).
I could not get any volts from the two pins. I did get 121 v from another source on the panel. I jumped two wires to the connector, thinking the inducer motor would come on, but instead I got an orange glow from somewhere (ignitor?).Should the motor come on right away?If my control panel was bad would everything not work, or could this connector be bad by itself?
The first thing that has to happen is the inducer fan starts up. Nothing else can happen until the inducer fan starts. The orange glow is the igniter. You have already jumpered between R and W on the terminal strip and you have 120 volts to the board plus you have a diagnostic light. Tells me you probably have a bad board.I am not sure what wires you are jumpering to get the igniter to come on but it doesn't sound like you are on the wires going to the inducer fan.