Operating a Nest thermostat is one of the easiest ways to optimize the day-to-day schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make improvements. But as you may expect, it won’t work well or at all if you see an error code show up. The exact error code supplies useful information about the underlying problem, something a trained technician can use to present solutions that much faster.

Let’s consider seven of the most likely error codes you might find on your Nest thermostat. We’ll explain the basics of each error code along with how you can solve it and the approximate cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can count on paying about $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware required to complete repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and is displayed when the power is disconnected from the system. As this is a critical power error, the thermostat will swap to the backup battery system. The error message will continue to be displayed until the problem 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 occurred further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will inspect electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring has to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure 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 detach the power and slowly check each wire, seeing to it that they are fully inserted into the connector with the proper amount of uncovered copper. When they find the damaged 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 break down and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will subsequently turn off. In the event the breakers are on, you can inspect a few other places before calling a professional technician.

Since this error can consume your thermostat’s battery, the first step could be providing enough power to figure out if this specific error code is what you’re facing. You can detach the thermostat from its base and supply power by using a USB cable. Assuming it presents error code 195, you should continue to visually examine components such as the wiring as well as your air conditioner’s air filter or drainage system. If you don’t uncover anything wrong with these components, it’s maybe best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical issue with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This can stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. The technician will carefully 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

Even though this error code isn’t critical, it might still prevent you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing 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 adjust the wiring itself if there is. If not, you can get a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 show up. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead be required 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 transported using the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s a good idea to switch the power off as soon as you can. You can then get a hold of a professional technician with the proper experience identifying and resolving electrical problems.

e73 – Critical

When your thermostat displays error code e73, it means that the Rc wire is not receiving power. This could be as simple as the breaker being turned off, but it can also be a problem with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure they’re not loose or damaged. If nothing appears to be out of place, it’s a good idea to get in touch with a local professional.