Installing a Nest thermostat is one of the best ways to optimize the day-to-day schedule of your comfort system. This smart thermostat can learn 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 appear. The precise error code provides useful information about the root of the problem, something a trained technician can use to offer solutions that much sooner.

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 can fix it and the approximate cost to do so. Don’t forget that while the costs will ultimately be dependent on the exact Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts needed to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is shut off. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will continue to be displayed until the issue is dealt with.

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

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first complete 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 looking at connectors.

They’ll disconnect the power and progressively check each wire, ensuring they are fully inserted into the connector with the proper amount of uncovered copper. When they pinpoint the malfunctioning connector, it can be replaced 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 delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will subsequently shut down. Presuming the breakers are on, you can inspect a handful of other places before calling a professional technician.

Because this error can deplete your thermostat’s battery, the first step could be supplying enough power to determine if this specific error code is what you’re facing. You can disconnect the thermostat from its base and provide power by using a USB cable. If it displays error code 195, you may continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can’t find anything wrong with these components, it’s maybe best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is getting more power than necessary. This may stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. A technician should cautiously inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it could still stop you from using the Nest thermostat like normal. Error code n260 concerns 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.

With installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 could 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 turn the power off as soon as you can. You can then contact a professional technician with the necessary experience diagnosing and solving electrical issues.

e73 – Critical

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

This will sometimes be as straightforward as the breaker being turned off, but it can also be a problem with the wiring. After switching off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure nothing is loose or damaged. If nothing appears to be out of place, it’s a good idea to contact a local professional.