12-07-2023 07:22 PM
My current system has both b and o wires, the nest thermostat has the o and b in one slot, how should I proceed?
Answered! Go to the Recommended Answer.
12-07-2023 10:09 PM
Just put the wire on B on the Nest C and the wire on O to the Nest O/B.
Your wires will be Rc, G, Y1, O/B and perhaps AUX/W2. Can you upload a picture of your current thermostat showing the connected wire.
AC Cooling Wizard
12-07-2023 09:57 PM
@otilioster , when you have a B terminal and an O terminal being used, you have a heat pump and the B terminal is used as power Common. This is very true when the thermostat does not have a C terminal.
AC Cooling Wizard
12-07-2023 10:03 PM
Thank you! So how would I wire it to the nest thermostat in this situation? Do I leave one of the wires disconnected?
12-07-2023 10:04 PM
12-07-2023 10:09 PM
Just put the wire on B on the Nest C and the wire on O to the Nest O/B.
Your wires will be Rc, G, Y1, O/B and perhaps AUX/W2. Can you upload a picture of your current thermostat showing the connected wire.
AC Cooling Wizard