Operating a Nest thermostat is one of the easiest ways to improve the daily schedule of your HVAC system. This smart thermostat can recognize your preferences and automatically make changes. But as you may expect, it won’t work correctly or at all if you see an error code show up. The exact error code supplies useful information about the root of the problem, something a professional technician can use to offer solutions that much quicker.

Listed below are seven of the most common error codes you might find on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you can fix it and the estimated cost to do so. Don’t forget that while the costs will ultimately be dependent on the specific 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 needed to wrap up repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and appears when the power is detached from the system. Because this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on display until the problem is dealt with.

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

They’ll detach the power and progressively check each wire, ensuring they are fully placed into the connector with the proper amount of bare copper. Once they pinpoint the damaged connector, it can be swapped for a new one.

e195 – Critical

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

As this error can consume your thermostat’s battery, the first step could be providing enough power to find out if this specific error code is what you’re facing. You can detach the thermostat from its base and supply power with a USB cable. Assuming 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 struggle to find anything wrong with these components, it will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This can stem from the breaker box, an error from the control board or through a bad connection in the thermostat. Your technician needs to meticulously inspect 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 might still prevent you from using the Nest thermostat how you prefer to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as the absence of 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 modify the wiring itself if there is. If not, you need a Nest Power Connector.

Due to installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector is 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 that’s the result of an overcurrent. If excessive power is sent inside the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you see this error code appear on your Nest thermostat and want to protect from electrical damage, it’s a good idea to turn the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience diagnosing and fixing 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 something 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 looks to be out of place, it’s a good idea to contact a local professional.