Using a Nest thermostat is one of the easiest ways to perfect the daily schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code on the display. The exact 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 common error codes you may find on your Nest thermostat. We’ll explain the basics of each error code on top of how you could solve it and the approximate cost to do so. Keep in mind that while the price will ultimately hinge on the specific Nest model, you can count on paying around $75-$200 for repairs. This should include travel and labor costs along with any specific hardware needed to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and shows up when the power is detached from the system. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will continue to be displayed until the problem is fixed.

Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection might have appeared further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A professional technician can examine electrical connections and wiring until they locate 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 make sure it’s not simply a software error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin inspecting connectors.

They’ll shut off the power and progressively inspect each wire, making sure they are fully inserted into the connector with the correct amount of exposed copper. When they locate the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely 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 subsequently shut down. In the event the breakers are on, you can search a few 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 determine if this specific error code is what you’re working with. You can detach the thermostat from its base and supply power with a USB cable. If it reveals error code 195, you can continue to visually inspect components such as 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 will likely be best to call 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 getting more power than necessary. This will sometimes stem from the breaker box, an error from the control board or thanks to a faulty connection in the thermostat. Your technician can cautiously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

Although this error code isn’t critical, it can still keep 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 getting sufficient power. You can check 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.

Due to 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 was already installed, you’ll instead have 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 stemming from an overcurrent. If excessive power is transported inside the Nest’s wiring, it can damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to turn the power off as soon as possible. You can then get a hold of a professional technician with the proper experience identifying and resolving electrical issues.

e73 – Critical

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

This could be as simple as the breaker being turned off, but it could also be something with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s time to contact a local professional.