Installing a Nest thermostat is one of the most convenient ways to improve the daily schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make changes. But as you may expect, it won’t work well or at all if you see an error code on the display. The exact error code offers useful information about the source of the problem, something a trained technician can use to offer solutions that much quicker.

Listed below are seven of the most common error codes you might discover on your Nest thermostat. We’ll explain the basics of each error code as well as how you could fix it and the estimated cost to do so. Remember that while the price will ultimately hinge on the precise Nest model, you can count on paying about $75-$200 for repairs. This should also cover travel and labor costs on top of any specific parts required to finish 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. Since this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on display until the problem is resolved.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection might have happened further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician should check electrical connections and wiring until they uncover the source of the problem.

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring needs to be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.

They’ll shut off the power and slowly look at each wire, ensuring they are fully inserted into the connector with the proper amount of exposed copper. After they pinpoint the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can shut down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will subsequently turn off. Assuming the breakers are on, you can examine a few other places before calling a professional technician.

As this error can drain your thermostat’s battery, the first step may be restoring enough power to find out if this specific error code is what you’re working with. You can detach the thermostat from its base and provide power by using a USB cable. If it displays error code 195, you can continue to visually examine components like the wiring as well as your air conditioner’s air filter or drainage system. If you don’t find anything wrong with these components, it will probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem with your Nest thermostat. More specifically, e103 will 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 figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it may still keep you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining adequate power. You can examine 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.

With installation of a Nest Power Connector, you might notice error code E297 show up. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already 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 originating from an overcurrent. If excess power is sent through the Nest’s wiring, it may damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to turn the power off as soon as you can. You can then contact a professional technician with the proper experience identifying and solving electrical malfunctions.

e73 – Critical

When your thermostat displays error code e73, it indicates that the Rc wire is not getting power.

This will sometimes be as easy as the breaker being shut off, but it could also be an issue 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 looks to be out of place, it’s best to contact a local professional.