Installing a Nest thermostat is one of the best ways to optimize the daily schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make adjustments. But as you might expect, it won’t work well or at all if you see an error code appear. The precise error code provides useful information about the underlying problem, something a knowledgeable technician can use to provide solutions that much sooner.

Listed below are seven of the most likely error codes you could encounter on your Nest thermostat. We’ll explain the basics of each error code as well as how you can fix it and the approximate cost to do so. Don’t forget that while the price will ultimately hinge on the specific 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 hardware 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 remain on the screen until the problem is fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring could have disconnected or become damaged, or a disconnection may have occurred further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician should check 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, the technician should reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin checking connectors.

They’ll disconnect the power and gradually look at each wire, seeing to it that they are fully placed into the connector with the correct amount of exposed copper. After they pinpoint the malfunctioning connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is particularly hot. The HVAC system can shut down and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will finally turn off. In the event the breakers are on, you can inspect a handful of other places before contacting a professional technician.

Because this error can deplete your thermostat’s battery, the first step may be providing enough power to figure out if this specific error code is what you’re working with. You can disconnect the thermostat from its base and supply power with a USB cable. If it presents error code 195, you may continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to 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 problem with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is receiving more power than needed. This will sometimes stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. A technician can carefully 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

Even though this error code isn’t critical, it may still stop you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting sufficient power. You can inspect 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.

With installation of a Nest Power Connector, you might notice error code E297 appear. This can be remedied 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

Similar to error code e103, e104 is a critical error originating from an overcurrent. If excess power is transported using the Nest’s wiring, it may damage internal components and may 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 possible. You can then get a hold of a professional technician with the proper experience detecting and resolving electrical damage.

e73 – Critical

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

This might be as straightforward as the breaker being turned off, but it may also be a problem 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 appears to be out of place, it’s time to get in touch with a local professional.