Operating a Nest thermostat is one of the best ways to perfect the day-to-day 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 exact error code supplies useful information about the source of the problem, something a knowledgeable technician can use to present solutions that much sooner.

Here are seven of the most common error codes you may find on your Nest thermostat. We’ll explain the basics of each error code along with how you might solve it and the estimated cost to do so. Remember that while the costs will ultimately hinge on the precise Nest model, you can anticipate paying around $75-$200 for repairs. This should include things like travel and labor costs as well as any specific hardware necessary to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is disconnected from the system. Because 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 could have disconnected or become damaged, or a disconnection could have occurred further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A knowledgeable technician should examine electrical connections and wiring until they uncover the source of the problem.

e294 – Critical

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

They’ll disconnect the power and gradually inspect each wire, ensuring they are fully inserted into the connector with the proper amount of uncovered copper. After they locate the damaged connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will eventually turn off. Presuming the breakers are on, you can search a handful of other places before calling a professional technician.

Since 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 dealing with. You can detach the thermostat from its base and deliver power with a USB cable. If it reveals error code 195, you may continue to visually inspect components like the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it’s maybe best to contact 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 necessary. This will sometimes stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. The technician can meticulously investigate and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it could still stop you from using the Nest thermostat how you want 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 obtaining adequate power. You can examine the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you need a Nest Power Connector.

With installation of a Nest Power Connector, you will sometimes 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 be required 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 excess power is transported using the Nest’s wiring, it may damage internal components and could 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 suggested to turn the power off as soon as possible. You can then contact a professional technician with the necessary experience diagnosing and solving electrical damage.

e73 – Critical

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

This could be as easy as the breaker being shut 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 inspect the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s a good idea to get in touch with a local professional.