Operating a Nest thermostat is one of the most convenient ways to optimize the day-to-day schedule of your HVAC system. This smart thermostat can learn 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 appear. The exact error code supplies useful information about the source of the problem, something a knowledgeable technician can use to offer solutions that much quicker.

Listed below are seven of the most likely error codes you might encounter on your Nest thermostat. We’ll walk you through the basics of each error code along with how you might address it and the estimated cost to do so. Don’t forget that while the price will ultimately be dependent on the specific Nest model, you can count on paying about $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts needed to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed when the power is disconnected from the system. Because 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 fixed.

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

e294 – Critical

Critical error code e294 appears 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 conduct a factory reset of your thermostat to ensure it’s not just a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin checking connectors.

They’ll detach the power and slowly check each wire, making sure they are fully attached into the connector with the correct amount of uncovered copper. Once they find the malfunctioning connector, it can be swapped for a new one.

e195 – Critical

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

Since this error can drain your thermostat’s battery, the first step might be providing enough power to find out if this specific error code is what you’re facing. You can separate the thermostat from its base and deliver power by using a USB cable. If it presents error code 195, you may continue to visually check components like the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to uncover anything wrong with these components, it’s maybe best to call a pro.

e103 – Critical

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

n260

While this error code isn’t critical, it might still prevent you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining adequate power. You can inspect the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you can get a Nest Power Connector.

Due to 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 have 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 that’s the result of an overcurrent. If too much power is sent inside 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 guard against electrical damage, it’s a good idea to switch the power off as soon as possible. You can then get in touch with a professional technician with the appropriate experience identifying and solving electrical malfunctions.

e73 – Critical

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

This will sometimes be as simple as the breaker being shut off, but it can also be an issue with the wiring. After turning 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 speak with a local professional.