Operating a Nest thermostat is one of the best ways to optimize the everyday schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make improvements. But as you might expect, it won’t work correctly or at all if you see an error code appear. The exact error code supplies useful information about the underlying problem, something a knowledgeable technician can use to present solutions that much sooner.

Here are seven of the most common error codes you may find on your Nest thermostat. We’ll review the basics of each error code on top of how you can fix it and the estimated cost to do so. Remember that while the costs will ultimately hinge on the precise Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs on top of any specific components 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 disconnected from the system. As 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 problem is resolved.

Losing power to your Nest thermostat can be for numerous reasons. The wiring may have disconnected or become damaged, or a disconnection may have happened further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A knowledgeable technician will inspect electrical connections and wiring until they find 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 complete a factory reset of your thermostat to make sure it’s not just a software problem. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin checking connectors.

They’ll shut off the power and gradually inspect each wire, making sure they are fully placed into the connector with the proper amount of exposed copper. After 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 shut down and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will finally turn off. Presuming the breakers are on, you can search a few other places before consulting a professional technician.

Because this error can deplete your thermostat’s battery, the first step could be providing enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and provide power by using a USB cable. If it reveals error code 195, you may 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 detect 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 malfunction with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This will sometimes stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. A technician needs to meticulously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Although this error code isn’t critical, it could still prevent you from using the Nest thermostat how you want to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from getting enough 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 need a Nest Power Connector.

Due to installation of a Nest Power Connector, you might notice error code E297 appear. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 stemming from an overcurrent. If too much power is sent inside the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you notice this error code show up on your Nest thermostat and want to protect from electrical damage, it’s recommended to switch the power off straightaway. You can then get a hold of a professional technician with the necessary experience identifying and solving electrical damage.

e73 – Critical

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

This could be as straightforward as the breaker being shut off, but it may also be something with the wiring. After switching 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 time to speak with a local professional.