Installing a Nest thermostat is one of the easiest ways to improve the daily schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make adjustments. But as you can expect, it won’t work well or at all if you see an error code on the display. The exact error code provides useful information about the root of the problem, something a professional technician can use to present solutions that much faster.

Here are seven of the most frequent error codes you might find on your Nest thermostat. We’ll review the basics of each error code on top of how you might address it and the projected cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can expect to pay around $75-$200 for repairs. This should include travel and labor costs as well as any specific components needed to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and shows up when the power is detached from the system. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on display until the issue is resolved.

Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection could have appeared further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A knowledgeable technician will examine 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 needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first perform a factory reset of your thermostat to make sure it’s not just a software issue. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin checking connectors.

They’ll disconnect the power and slowly check each wire, seeing to it that they are fully placed into the connector with the correct amount of bare copper. Once they pinpoint the malfunctioning connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can fail and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will eventually power down. In the event the breakers are on, you can examine a handful of other places before consulting a professional technician.

Since this error can consume your thermostat’s battery, the first step might be supplying enough power to figure out if this specific error code is what you’re working with. You can separate the thermostat from its base and deliver power by using a USB cable. Assuming it displays error code 195, you may continue to visually examine components including 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 will probably be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical malfunction with your Nest thermostat. More specifically, e103 will 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 thanks to a faulty connection in the thermostat. A technician should cautiously examine 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

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 the absence of one can block your Nest from getting 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 might notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead need 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 could damage internal components and may 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 shut the power off as soon as possible. You can then get in touch with a professional technician with the appropriate experience diagnosing and resolving electrical issues.

e73 – Critical

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

This could be as simple as the breaker being turned off, but it may also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s best to speak with a local professional.