Installing a Nest thermostat is one of the easiest ways to improve the everyday schedule of your comfort system. This smart thermostat can learn your preferences and automatically make improvements. But as you might expect, it won’t work properly or at all if you see an error code on the display. The precise error code supplies useful information about the underlying problem, something a trained technician can use to provide solutions that much faster.

Here are seven of the most frequent error codes you could encounter on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you can fix it and the approximate cost to do so. Remember that while the costs will ultimately hinge on the specific Nest model, you can count on paying between $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware required to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed when the power is detached from the system. As this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on display until the problem is dealt with.

Losing power to your Nest thermostat can be for numerous reasons. The wiring may have disconnected or become damaged, or a disconnection could have happened further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A professional technician should examine electrical connections and wiring until they find the source of the problem.

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring should be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first perform 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 begin inspecting connectors.

They’ll detach the power and gradually look at each wire, making sure they are fully placed into the connector with the correct amount of bare copper. When they pinpoint the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly hot. The HVAC system can shut down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will finally shut down. Presuming the breakers are on, you can check a handful of other places before consulting a professional technician.

Since 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 through a USB cable. Assuming it displays error code 195, you should 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 likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 signifies 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 may stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. A technician needs to carefully investigate 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

Even though this error code isn’t critical, it might still keep you from using the Nest thermostat how you prefer 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 obtaining enough power. You can examine the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you need a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 appear. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead have 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 excessive power is being delivered through the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you see this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s suggested to shut the power off as soon as you can. You can then get a hold of a professional technician with the proper experience diagnosing and fixing electrical issues.

e73 – Critical

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

This may be as easy as the breaker being shut off, but it can 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 appears to be out of place, it’s a good idea to contact a local professional.