Wyze Thermostat Powering Off At End of Heat Cycle

Recently installed the Wyze Thermostat and noticed during the end of the heating cycle the thermostat powers down and restarts. It seems to work ok after but not sure why it is doing this or if it can lead to other problems. I am also having issues with it disconnecting to the cloud :cloud: with line through it, but am waiting on Wyze Support to resolve that issue.

Does anyone know what would cause this? I’m thinking it is has something to do with the older furnace/control board and how the c wire is connected.

Show your wiring.

Speadie, you helped me wire this in an earlier post. I’ll send the pics from earlier but if you remember, I was the one that had a blue wire that was not connected and ended up connecting it to the white wire coming from the ax and a blue wire going to the frame by transformer, which is connected to a ground and the 24v on the transformer.


Your wiring looks correct. There is a possibility that your limit switches or rollout switches are being tripped and the power is being cut to your system. This is a safety feature. You should probably watch the furnace when it is running to see if there is an abnormal flame pattern, and/or get an HVAC technician to look at your system. With a battery powered thermostat, and no micro-controller lockout these issues often go unnoticed until they get so severe that the system no longer runs at all.

Yeah, I’m trying to avoid calling a HVAC person but I might have to. It just seems strange that it normally happens just as the heat reaches the desired temp.

Could be the 24v transformer is under rated?
What is 24v rated?

No idea. How do I determine that?

Probably on label under the live wire (black). Do not touch it.

If you connect a voltage meter between Rc and C at the twist knobs going to thermostat.
You mentioned it was 27V.
2 Qs
At the end of heat cycle when Wyze off itself, what the voltage reading?

At the C knob The re are two wires I can see from pic. One is blue wire goes to thermostat.
Where is the white wire goes to?

I will have to check the voltage at the end of the heat cycle later.

The white wire goes to the Central Air compressor outside. The thick Blue wire goes to the frame where the transformer is mounted and also connects to a green wire that goes to a ground. The thin blue wire not connected in the pic is the thermostat wire that was connected after the photo was taken.

Also post a pic of your Wyze Tstat final wiring.

Will do. I’m away now, so probably not until later today or tomorrow.