Using a Nest thermostat is one of the best ways to perfect the daily schedule of your HVAC system. This smart thermostat can recognize your preferences and automatically make changes. But as you might expect, it won’t work correctly or at all if you see an error code appear. The specific error code provides useful information about the root of the problem, something a trained technician can use to offer solutions that much quicker.

Here are seven of the most frequent error codes you may find on your Nest thermostat. We’ll walk you through the basics of each error code along with how you could solve it and the approximate cost to do so. Keep in mind that while the price will ultimately be dependent on the exact Nest model, you can expect to pay between $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to newer 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 display until the issue is dealt with.

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

e294 – Critical

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

They’ll detach the power and progressively look at each wire, making sure they are fully inserted into the connector with the proper amount of bare copper. After they pinpoint the damaged connector, it can be swapped 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 persists, the backup battery in your thermostat depletes and the thermostat will finally turn off. Presuming the breakers are on, you can search a few other places before contacting a professional technician.

As this error can consume your thermostat’s battery, the first step may be providing enough power to determine 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. Assuming it reveals 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 will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than what is safe and normal. This may stem from the breaker box, an error from the control board or through a bad connection in the thermostat. Your technician will cautiously examine 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 can still stop 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 obtaining adequate power. You can examine the Nest’s C connector for the presence of a C wire and modify 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 appear. 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 stemming from an overcurrent. If too much power is being delivered through the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to shut the power off as soon as you can. You can then contact a professional technician with the appropriate experience identifying and solving electrical malfunctions.

e73 – Critical

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

This may be as straightforward as the breaker being shut off, but it can also be an issue with the wiring. After turning off the power to your HVAC system and thermostat, you can visually examine the wires to make sure they’re not loose or damaged. If nothing appears to be out of place, it’s a good idea to get in touch with a local professional.