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

Here are seven of the most frequent error codes you may encounter on your Nest thermostat. We’ll review the basics of each error code as well as how you might fix it and the approximate cost to do so. Remember that while the costs will ultimately hinge on the exact Nest model, you can count on paying between $75-$200 for repairs. This should also cover travel and labor costs along with any specific components necessary to complete repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears when the power is disconnected from the system. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on the screen until the issue is fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection may have appeared further along in the electrical system. This may be the circuit breaker, fuse box or system switch. A professional technician should check electrical connections and wiring until they find the root of the problem.

e294 – Critical

Critical error code e294 shows up 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 complete a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and progressively check each wire, ensuring they are fully inserted into the connector with the correct amount of uncovered copper. When they find the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can fail and stop sending power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally shut down. Presuming the breakers are on, you can examine a couple of other places before calling a professional technician.

Since this error can consume your thermostat’s battery, the first step may be supplying enough power to determine if this specific error code is what you’re working with. You can detach the thermostat from its base and deliver power by using a USB cable. If it reveals error code 195, you can continue to visually check components like 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 probably 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 receiving more power than needed. This can stem from the breaker box, an error from the control board or through a defective connection in the thermostat. The technician needs to carefully 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

Although this error code isn’t critical, it may still stop 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 missing 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 need a Nest Power Connector.

During installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead be required to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Just like error code e103, e104 is a critical error originating from an overcurrent. If excess power is being delivered using the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to protect from electrical damage, it’s recommended to switch the power off straightaway. You can then get a hold of a professional technician with the necessary experience diagnosing and solving electrical problems.

e73 – Critical

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

This might be as easy as the breaker being turned off, but it can also be an issue with the wiring. After switching off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s time to speak with a local professional.