Thermostat shows E8 and reports an internal temperature sensor error; room temperature reading is blank or frozen.

Safety first: Turn off power to the HVAC system at the breaker before removing the thermostat display.

• Power cycle the thermostat: Gently remove the Wyze thermostat display from the wall plate, wait 30 seconds, then reattach it to force a reboot. Restore power and check if E8 clears.
• Check for environmental issues: Ensure the thermostat is not installed in direct sunlight, above a heat register, or on an exterior wall that may cause extreme temperatures. While this won’t usually cause E8, it can stress the sensor.
• Inspect for damage: Look for signs of liquid damage, cracks, or warping on the thermostat body. If present, the internal sensor or board is likely compromised.
• Update firmware: In the Wyze app, check for thermostat firmware updates and apply any available updates, then reboot the thermostat again.
• Replace thermostat if needed: If E8 persists after reboot and firmware update, the internal sensor assembly is likely failed and the thermostat display should be replaced.