If there is a common wire installed the nest thermostat will not power share. Turn off power to your system at the breaker box or system switch.

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Nest thermostat no power. The thermostat has been working for years. Learn about the common wire and why a nest thermostat may need one in most cases google nest thermostats can charge their built in battery using your systems heating and cooling wires. 2 red into rh two read more. Turn off the power to your heating and cooling. Nest button doesnt click quite right or the thermostat just wont sit right on the base. We cover all these problems with the nest 3rd generation thermostat and give you.
I believe my heat and cooling is 1 stage. No power to w 1 wire detected. My nest thermostat not working message e4 no power to rh. But two sets of 4 wires as follows. If your system works as it should with your old thermostat your nest thermostat may be damaged and needs to be replaced. Cooling is always or intermittently on when the nest thermostat is not calling for cooling the nest thermostat display background is black.
No power to the r wire. Your nest thermostat is physically detecting a wire in the w 1 heating connector but isnt detecting any power to it. Cooling is not on or turns off intermittently when the. When x w1 or w2 is an aux wire. Some heat pump installations may have the auxiliary heat connection labelled as x w1 or w2 on the thermostat. You should verify that the x wire on the old thermostat is not a common wire.