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1. If you are replacing a thermostat, tell me what all wires went to on old thermostat.
2.If not replacing, just installing, we will need to look in the furnace and se what each connects to in furnace
OK now in original question you stated you have 1 red, 2 greens, a W and a Y
IN second reply you state Red,2 yellows and a green.
Help me out here.I am depending on you to be my hands as eyes as we go through this.
So you have the RED to RC and RH that is good
The yellow that went to Y to Y1 that is good
The yellow that went to W to W1 that is good
The green that went to G to G That is good
Now do you have an unused wire we can use for Common (B/C)?
On old thermostat did you have either a C terminal or a B terminal and if so what wire was connected to it?
OK the XL824 requires us to have 24 volts where some thermostats are battery powered.
This means we have to have a wire from the Hot side of transformer in furnace as well as the COMMON side of transformer.
So what we are going to have to do is use one of those "extra" wires and connect it to B/C on thermostat and "Common" in furnace.
If you can give me model on the indoor furnace I will help you determine where to connect that "extra" wire in the furnace.
Excellent give me a few moments to fin da manual on furnace
OK remove the panels on furnace and you will find a computer board inside where all of the thermostat wires connect.
On that board you will see the terminals marked W,R,G,COM and Y.
The yellow you have connected to W1 at thermostat should go to W
The Red you have connected to RC/RH at thermostat should go to R
The Green that you have connected to G at thermostat should go to G
The yellow you have connected to Y1 should go to Y.
Then we will connect one of the blacks or the extra green to B/C at thermostat and to CO
Mm at furnace board.
Se link below
Should say "Then we will connect one of the blacks or the extra green to B/C at thermostat and to COM on furnace board
Makes no difference.You just have to verify you are using black from same set of wires in both places
Yes one goes to the outdoor unit.The other may go to a humidifier or something. Just add the green and connect other end to BC at thermostat
OK look on that control board and see if there is a small 3 or 5 amp fuse. Remove it and see if it got blown when you first started messing with wires.
Location on your board
Do you have all panels back on furnace? If so do you have a volt meter so we can do some troubleshooting?
You must put panels back on to have power to thermostat as there is a door switch held in by blower panel.
Put panels on and we will go from there if still no display
OK remove panel and hold door switch in, Then check between R and C on furnace board and see if we have 24vac between them
We will need a working meter to troubleshoot. Put panel back on.Go to thermostat and touch the red and green that is going to G and see if blower comes on