Installing a Nest thermostat is one of the easiest ways to perfect the day-to-day schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make adjustments. But as you can expect, it won’t work well or at all if you see an error code appear. The exact error code offers useful information about the underlying problem, something a professional technician can use to provide solutions that much quicker.

Here are seven of the most frequent error codes you may find on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can fix it and the projected cost to do so. Keep in mind that while the price will ultimately be dependent on the specific Nest model, you can anticipate paying around $75-$200 for repairs. This should include things like travel and labor costs on top of any specific parts necessary to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is detached from the system. Because this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on the screen 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 might have appeared further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician can check electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring has to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not just a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and gradually check each wire, making sure they are fully attached into the connector with the correct amount of exposed copper. When they locate the malfunctioning connector, it can be replaced for a new one.

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will finally power down. Presuming the breakers are on, you can search a few other places before consulting a professional technician.

Since this error can deplete your thermostat’s battery, the first step might be supplying enough power to figure out if this specific error code is what you’re dealing with. You can separate the thermostat from its base and supply power through a USB cable. If it presents error code 195, you should continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to find anything wrong with these components, it will probably be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This can stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. A technician needs to cautiously investigate and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it could still prevent you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from getting sufficient power. You can check the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you can get a Nest Power Connector.

During installation of a Nest Power Connector, you may notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead need to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Similar to error code e103, e104 is a critical error originating from an overcurrent. If too much power is transported using the Nest’s wiring, it can damage internal components and can even be a fire hazard. If you see this error code appear on your Nest thermostat and want to guard against electrical damage, it’s recommended to switch the power off as soon as you can. You can then get a hold of a professional technician with the proper experience detecting and solving electrical issues.

e73 – Critical

When your thermostat displays error code e73, it means that the Rc wire is not receiving power. This may be as straightforward 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 check the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s best to contact a local professional.