Operating a Nest thermostat is one of the most convenient ways to optimize the day-to-day schedule of your comfort system. This smart thermostat can be taught 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 precise error code offers useful information about the source of the problem, something a professional technician can use to provide solutions that much quicker.

Listed below are seven of the most likely error codes you may find on your Nest thermostat. We’ll review the basics of each error code on top of how you could fix it and the projected cost to do so. Keep in mind that while the price will ultimately be dependent on the precise Nest model, you can count on paying around $75-$200 for repairs. This should also cover travel and labor costs on top of any specific hardware required to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is shut off. Since this is a critical power error, the thermostat will change 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 may 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 professional technician should check electrical connections and wiring until they find the root of the problem.

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to ensure it’s not simply a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin looking at connectors.

They’ll shut off the power and gradually look at each wire, making sure they are fully attached into the connector with the correct amount of exposed copper. Once they locate the malfunctioning connector, it can be replaced for a new one.

e195 – Critical

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

Because this error can drain your thermostat’s battery, the first step could be supplying enough power to figure out if this specific error code is what you’re dealing with. You can separate the thermostat from its base and supply power through a USB cable. In the event 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 struggle to uncover anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than what is safe and normal. This may stem from the breaker box, an error from the control board or through a bad connection in the thermostat. Your technician needs to cautiously inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks 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 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining 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.

During installation of a Nest Power Connector, you may notice error code E297 appear. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 through the Nest’s wiring, it can damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s suggested to shut the power off as soon as you can. You can then contact a professional technician with the necessary experience identifying and resolving electrical problems.

e73 – Critical

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

This could be as straightforward as the breaker being shut off, but it could also be an issue with the wiring. After switching 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 seems to be out of place, it’s time to get in touch with a local professional.