- Heating or cooling is always on, and won’t turn off
- Heating or cooling doesn’t turn on
- You repeatedly see a Delayed or Starts in message on your Nest thermostat’s screen (for example: “Heating is delayed for 2:30 mins” or “Starts in 2:30 mins”)
- Heating or cooling turns on and off intermittently or unexpectedly
- The system fan is always running or won’t turn on
- The system fan turns on and off unexpectedly or intermittently
- Your system is making strange noises: chattering, stuttering, clicking or thumping- this can be caused by your system turning on and off rapidly