No C terminal on my air handler.
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No C terminal on my air handler.
I have an old Trane system (single stage heat pump) and want to install a WiFi thermostat, but need a "C" wire to power it.
There is no such terminal on my air handler. There is 24V across the red/blue and red/green terminals. Can I just install a jumper between either the blue or green and the C terminals?
There is no such terminal on my air handler. There is 24V across the red/blue and red/green terminals. Can I just install a jumper between either the blue or green and the C terminals?
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Thanks for the reply.
I cannot get to the transformer w/o a major dismantle of the air handler, so I have attached a drawing of the connections.
There was also a schematic in the AH so I inserted the relevant portion of it into the drawing. As you can see, the blue and green wires come off one end of the transformer secondary and the red wire comes of the other.
I'm wondering if I can attach a C wire to the blue/green side.
(Not sure if I got the drawing attached. I'll post and see.)
I cannot get to the transformer w/o a major dismantle of the air handler, so I have attached a drawing of the connections.
There was also a schematic in the AH so I inserted the relevant portion of it into the drawing. As you can see, the blue and green wires come off one end of the transformer secondary and the red wire comes of the other.
I'm wondering if I can attach a C wire to the blue/green side.
(Not sure if I got the drawing attached. I'll post and see.)
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Looks like the picture posted. However the bottom was cropped a little. The box at the bottom shows the thermostat connections. The fine lines you see at W/Y and RC/RH at the are jumpers.
The box on the left is the air handler connections.
The box on the left is the air handler connections.
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I have an unused wire (which happens to be blue, by the way) in the cable running to my thermostat. If the blue is the common, then I should be able to connect the AH end of the wire to the B terminal and the other to the C terminal on the Tstat. Correct?
BTW here is the entire schematic.
BTW here is the entire schematic.
#7
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On a Trane....B is the Common wire. You'll see it goes from the transformer right to the B terminal on the low voltage wiring strip.
On a Trane....B is the Common wire. You'll see it goes from the transformer right to the B terminal on the low voltage wiring strip.
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Got it!
Thank you Skaggsje & Pete.
My local utility is offering a rebate on Honeywell, Ecobee and Nest thermostats. I thought I'd take the opportunity to upgrade. Now I know I can do it.
John
Thank you Skaggsje & Pete.
My local utility is offering a rebate on Honeywell, Ecobee and Nest thermostats. I thought I'd take the opportunity to upgrade. Now I know I can do it.
John