Unplug it from the wall then plug it back in to see if that helps. Double check whether the nest display is ideally placed to the based check whether the system gets enough power make sure the system is compatible check the thermostats wiring find whether the fuse in the system blown out look whether the.
Problems With Nest Thermostat 4 0 Mike Mchargue
Nest not charging on wall. If the nest thermostat isnt charging after power has been restored to your home check your breaker box to see that all switches are in the on position. After an hour of charging return the nest to the wall and it should resume working. It should be around 24v from the red wire r. To solve this issue you must check the following. It will deplete if the system is off for too long. Check on the nest itself under settingstechnical infopower.
If your nest thermostat is off and wont turn on take the thermostat off the base and charge it using a usb cord plugged into a wall charger or a computer. Do not use a. Do not try to restart your thermostat while its still connected to a computer for charging. They didnt go into detail why but if nest says dont do it do not do it. This step will take about 1 hour to fully charge the nest. I would check the furnace wiring to make sure they match up and the common wire is the correct wire.
If the voltage is low there may be a wiring problem and your nest may not be charging properly. If not you may need to call in. Pull off the nest display and use the usb port on the back to charge it with a usb cable and wall charger. At this time the battery may still not be strong enough to get the nest connected to your networkthis is normal and eventually the nest will charge itself up enough to return itself to the network. If it works properly with a normal thermostat then it should work okay with the nest you need a common wire. The nest appears only to charge when the ac system is running robbing a small amount to charge itself.
Regular thermostat it can work fine with battery ones. If you have fuses make sure none have been blown and need replacing. After it starts up plug the usb cable back in to finish charging the nest. Depending on the model you have it will be either mini or micro usb.