Hi livepony55,
Oh no! Let's sort this out.
- The N73 error code means that the thermostat detects the wire mechanically but not electrically. If the system works normally, you don’t need to take any action but might want to contact an HVAC technician to check your system. However, here are some steps you might want to try:
- Turn off any available power source.
- Remove the thermostat display from its base.
- Remove the wire in question.
- Straighten, strip, and reseat the wire into its appropriate terminal on the base.
- Place the thermostat display back to its base.
- Turn the power source back on.
- Furnace Heads-Up alerts you when your Google Nest Thermostat detects a problem with your forced air heating system. To troubleshoot Furnace Heads-Up message, run a quick system test. If your furnace doesn't heat for over 15 minutes, you'll receive a message on your Nest thermostat, Google Home app, and Nest Home Report.
The Nest Learning Thermostat 3rd Generation displays a green blinking light during charging, which should stop blinking and remain solid green once attached to the wall plate. If the light continues to blink even after the thermostat is attached, it may indicate a problem with the charging process or the connection between the thermostat and the wall plate. Follow these:
- The thermostat should be securely attached to the wall plate, with the pins making proper contact. If the connection is loose, it may cause a blinking green light. To ensure a secure connection, remove the thermostat from the wall plate and reattach it.
- Restart the thermostat by disconnecting it from the wall plate, turn off the power to the HVAC system, wait a few minutes, then re-on the power and reattach the thermostat to the wall plate, checking if the green light stops blinking and remains solid green.
- Ensure your thermostat's power source is functioning properly, the wiring is connected correctly, and the circuit breaker or fuse for the HVAC system is not tripped.
Let us know if that helps.
Best,
Zoe