Installing a Nest thermostat is one of the best ways to improve the everyday schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make adjustments. But as you might expect, it won’t work correctly or at all if you see an error code appear. The specific error code offers useful information about the underlying problem, something a knowledgeable technician can use to present 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 on top of how you could fix it and the estimated cost to do so. Remember that while the price will ultimately be dependent on the exact Nest model, you can anticipate paying between $75-$200 for repairs. This should include travel and labor costs as well as any specific hardware necessary to complete repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and shows up 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 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 your electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician should inspect electrical connections and wiring until they locate the root of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should 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 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 detach the power and slowly check each wire, seeing to it that they are fully placed into the connector with the correct amount of uncovered copper. After they locate the problem 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 sending power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally shut down. Presuming the breakers are on, you can examine a couple of other places before consulting a professional technician.

Because this error can consume your thermostat’s battery, the first step could be supplying enough power to determine if this specific error code is what you’re working with. You can separate the thermostat from its base and supply 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 struggle to detect 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 issue with your Nest thermostat. More specifically, e103 can 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 through a bad connection in the thermostat. The technician can cautiously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Although this error code isn’t critical, it can still keep you from using the Nest thermostat how you want to. 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 adequate power. You can inspect the Nest’s C connector for the presence of a C wire and modify 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 be displayed. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was 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 stemming from an overcurrent. If excessive 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 appear on your Nest thermostat and want to guard against electrical damage, it’s suggested to turn the power off straightaway. You can then get in touch with a professional technician with the necessary experience diagnosing and resolving electrical malfunctions.

e73 – Critical

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

This might be as simple as the breaker being turned off, but it may also be a problem with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s time to speak with a local professional.