Using a Nest thermostat is one of the best ways to optimize the everyday schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make adjustments. But as you can expect, it won’t work properly or at all if you see an error code on the display. The exact error code provides useful information about the source of the problem, something a professional technician can use to provide solutions that much sooner.
Here are seven of the most likely error codes you could find on your Nest thermostat. We’ll explain the basics of each error code on top of how you can solve it and the approximate cost to do so. Don’t forget that while the costs will ultimately hinge on the specific Nest model, you can count on paying around $75-$200 for repairs. This should include travel and labor costs along with any specific hardware necessary to finish repairs.
e298 – Critical
This critical error code is limited to the latest models of the Nest thermostat and appears when the power is detached from the system. Since this is a critical power error, the thermostat will change to the backup battery system. The error message will continue to be displayed until the issue is resolved.
Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection could have appeared further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician should inspect electrical connections and wiring until they find the root of the problem.
e294 – Critical
Critical error code e294 shows up when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to ensure it’s not merely a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start checking connectors.
They’ll disconnect the power and gradually check each wire, ensuring they are fully placed into the connector with the proper amount of uncovered copper. After they find the damaged connector, it can be exchanged for a new one.
e195 – Critical
This critical error code can show up when the weather outside is severely hot. The HVAC system can break down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally power down. Assuming the breakers are on, you can search a handful of other places before consulting a professional technician.
Because this error can drain your thermostat’s battery, the first step might be supplying enough power to find out if this specific error code is what you’re facing. You can detach the thermostat from its base and deliver power by using a USB cable. In the event it reveals error code 195, you can continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to detect anything wrong with these components, it’s maybe best to call a pro.
e103 – Critical
Another critical error code, e103 signifies an electrical malfunction with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than what is safe and normal. This can stem from the breaker box, an error from the control board or through a defective connection in the thermostat. A technician can meticulously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.
While this error code isn’t critical, it may still keep you from using the Nest thermostat how you want to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from receiving enough power. You can check the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you’ll need a Nest Power Connector.
Due to installation of a Nest Power Connector, you might notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead have to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.
e104 – Critical
Like error code e103, e104 is a critical error that’s the result of an overcurrent. If excessive power is being delivered inside the Nest’s wiring, it may damage internal components and can even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s suggested to shut the power off as soon as possible. You can then contact a professional technician with the appropriate experience detecting and fixing electrical damage.
e73 – Critical
When your thermostat displays error code e73, it means that the Rc wire is not receiving power.
This might be as easy as the breaker being switched off, but it may also be something with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing seems to be out of place, it’s best to get in touch with a local professional.