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Let e make sure I understand everything.
1.Lookslike your upstairs fan is bad and you have ordered a motor.So that will correct that problem
2.Downstars contactor does not pull in by downstairs thermostat but it will from upstairs tstat with wires swapped.
Is this correct?
Great Lets start by eliminating the thermostat. Reconnect the wires to proper outdoor units.Go to downstairs thermostat.Remove front cover. Loosen screws where wires connect to terminals and touch the R wire to the Y wire and tell me if contactors pull in and unit comes on.
What is model on the Tstat? Do you have a picture showing the wires?
If you have a paper clip icon on your page you can attach using that link.Or
You can upload the pictures using the tiny pic site .
Here is a link to the site.
Click on Browse , select the file from your folder.then click UPLOAD NOW.
They will give you a quote to enter in the box to verify you are a human.Enter the quote and click UPLOAD NOW
You will see your picture on right side of screen.
Then copy the link URL for email & IM
Paste that link here on the site.
Tell me if this is the right thermostat and if so what color wires are connect to what terminals
Remove these screws to expose actual wires from furnace to thermostat
what color wires are connect to what terminals
Excellent. Use a jumper or loosen screws and touch the red wire (Rh/RC)to the yellow wire (Y)and see if outside unit comes on.
OK next jump R to G Red to green and tell me if indoor blower comes on
OK go ahead and put thermostat back together.We have an electrical issue .Thermostat not getting 24v signal from furnace.Go to indoor unit and give me model on indoor furnace
OKI want you to open bottom blower panel and see if there if a small 3 or 5 amp fuse on furnace control board.If so remove it and see if it is blown.
Board may look like this
Is this light on, off or flashing?
Ok if you will look at the chart on board that means we have no power to board.Push door button in and tell me if light comes on
Ok lets look in the drain line and see if maybe there is a float switch that might be breaking circuit to thermostat.If so lift up on switch and call for ac and let e know if unit comes on.
See if indoor fan will come on with float switch lifted
OK but thermostat is still calling for ac Yes?
OK somewhere we are losing the 24 volts from furnace to thermostat.May be a bad wire nut connection or something.Does that float switch wire into the red wire?If so might try bypassing it
Do you have a meter for checking voltage?WE are losing the 24 volts somewhere that tells thermostat to signal unit to come on
You disconnect wires to float and twisted red wires together right?
Lets check between R and C on furnace control terminal board where thermostat wires hook up (Door switch held in of course)
OK just making sure.I have had people twist float switch wires together.Lets check 24v out of furnace at R and C
OK now do this.Turn thermostat to call for AC or FAN and come back to furnace board and check between G and C for the 27 volts
Go back to thermostat.Put the alligator jumper from R to G and check again
WE have a break in that red wire somewhere between furnace and thermostat
Yours does not have the fuse. We have verified we have 27v leaving the furnace.
Red goes to RH/RC at thermostat
Thermostat is basically just like a light switch
On call for fan R and G circuit close and send the 24v back to furnace
On call for AC RH/RC, Y and G all close and send circuit to furnace blower and outdoor contactor.
Jumping R to G at thermostat is bypassing thermostat and should close the circuit back to G
Somewhere between where the red leaves R at furnace we are losing it or in other words have a break in the wire before it gets to RH/RC at thermostat
If you have a long piece of wire. Connect it to R at furnace and RC/RH .
Another thing you can try is put the alligator jumper directly from R to G on board and see if indoor fan come son
Yes and see if blower comes on
That proves as I said, there is a break in that red wire before it gets to thermostat
It should.I will stand by
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