Using a Nest thermostat is one of the most convenient ways to optimize the day-to-day schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make adjustments. But as you may expect, it won’t work properly or at all if you see an error code on the display. The precise error code offers useful information about the root of the problem, something a knowledgeable technician can use to offer solutions that much sooner.

Listed below are seven of the most likely error codes you could discover on your Nest thermostat. We’ll review the basics of each error code on top of how you could solve it and the estimated 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 also cover travel and labor costs as well as any specific components required to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is shut off. As this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on the screen until the problem is fixed.

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

e294 – Critical

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

They’ll detach the power and progressively check each wire, making sure they are fully placed into the connector with the proper amount of uncovered copper. After they locate the malfunctioning 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 fail and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will eventually shut down. In the event the breakers are on, you can check a few other places before consulting a professional technician.

Because this error can deplete your thermostat’s battery, the first step may be supplying enough power to find out if this specific error code is what you’re facing. You can separate the thermostat from its base and supply power by using a USB cable. Assuming it reveals error code 195, you can continue to visually inspect components like the wiring as well as your air conditioner’s air filter or drainage system. If you can’t 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 error with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than necessary. This will sometimes stem from the breaker box, an error from the control board or thanks to a faulty connection in the thermostat. A technician should cautiously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it might still keep 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 receiving sufficient 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 need a Nest Power Connector.

Due to installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be dealt with 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

Similar to error code e103, e104 is a critical error that’s the result of an overcurrent. If excessive power is being delivered using the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s recommended to shut the power off straightaway. You can then get in touch with a professional technician with the necessary experience diagnosing and fixing electrical problems.

e73 – Critical

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

This will sometimes be as easy as the breaker being turned off, but it may also be an issue with the wiring. After turning off the power to your HVAC system and thermostat, you can visually check the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s time to get in touch with a local professional.