Using a Nest thermostat is one of the best ways to improve the day-to-day schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make changes. But as you may expect, it won’t work properly or at all if you see an error code appear. The precise error code offers useful information about the underlying problem, something a trained technician can use to present solutions that much sooner.

Listed below are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll walk you through the basics of each error code along with how you could solve it and the projected cost to do so. Keep in mind that while the costs will ultimately depend on the exact Nest model, you can count on paying between $75-$200 for repairs. This should include travel and labor costs along with 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 detached from the system. Because this is a critical power error, the thermostat will change 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 might have disconnected or become damaged, or a disconnection might have appeared further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will examine electrical connections and wiring until they locate the root of the problem.

e294 – Critical

Critical error code e294 is displayed 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 conduct a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin checking connectors.

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

e195 – Critical

This critical error code can surface when the weather outside is particularly 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 shut down. Presuming the breakers are on, you can inspect a couple of other places before consulting a professional technician.

As this error can consume your thermostat’s battery, the first step could be supplying enough power to figure out if this specific error code is what you’re working with. You can detach the thermostat from its base and supply power by using a USB cable. If it reveals error code 195, you should continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can’t find anything wrong with these components, it will likely be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than what is safe and normal. This can stem from the breaker box, an error from the control board or thanks to a bad connection in the thermostat. A technician can meticulously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it can still keep 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 not having one can block your Nest from getting adequate 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’ll need 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 originating from an overcurrent. If too much power is being delivered inside the Nest’s wiring, it can damage internal components and can 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 a good idea to turn the power off as soon as you can. You can then contact a professional technician with the appropriate experience detecting and resolving electrical problems.

e73 – Critical

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

This could be as easy as the breaker being shut off, but it could also be an issue with the wiring. After shutting 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 seems to be out of place, it’s time to speak with a local professional.