Using a Nest thermostat is one of the easiest ways to improve the day-to-day schedule of your HVAC system. This smart thermostat can recognize your preferences and automatically make changes. But as you can expect, it won’t work properly or at all if you see an error code appear. The precise error code provides 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 might find on your Nest thermostat. We’ll review the basics of each error code as well as how you could address it and the estimated cost to do so. Don’t forget that while the costs will ultimately depend on the precise Nest model, you can expect to pay around $75-$200 for repairs. This should include things like travel and labor costs as well as any specific components needed to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and shows up 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 continue to be displayed until the issue is fixed.

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

e294 – Critical

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

They’ll shut off the power and progressively look at each wire, ensuring they are fully inserted into the connector with the proper amount of bare copper. Once they locate the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will subsequently shut down. Assuming the breakers are on, you can check a couple of other places before consulting a professional technician.

Because this error can drain your thermostat’s battery, the first step might be providing enough power to determine if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and deliver power through a USB cable. If it displays error code 195, you should continue to visually check components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t find anything wrong with these components, it’s maybe best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem 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 because of a bad connection in the thermostat. The technician should carefully 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

Even though this error code isn’t critical, it could still prevent 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 receiving adequate 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 can get a Nest Power Connector.

Due to installation of a Nest Power Connector, you may notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already 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 that’s the result of an overcurrent. If excess power is being delivered inside the Nest’s wiring, it may damage internal components and can 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 recommended to shut the power off straightaway. You can then contact a professional technician with the necessary 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 switched off, but it could also be a problem with the wiring. After switching 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 seems to be out of place, it’s best to speak with a local professional.