Using a Nest thermostat is one of the best ways to optimize the everyday schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make improvements. But as you can expect, it won’t work properly 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 professional technician can use to present solutions that much sooner.

Listed below are seven of the most frequent 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 solve it and the approximate cost to do so. Don’t forget that while the price will ultimately be dependent on the exact Nest model, you can expect to pay around $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 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 issue is dealt with.

Losing power to your Nest thermostat can be for several reasons. The wiring may have disconnected or become damaged, or a disconnection may have appeared further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician can examine 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 needs to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software error. If that doesn’t work, they’ll check 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 proper amount of exposed copper. When they pinpoint 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 particularly hot. The HVAC system can fail and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally turn off. Assuming the breakers are on, you can search a couple of other places before consulting a professional technician.

Because this error can consume your thermostat’s battery, the first step might be supplying enough power to figure out if this specific error code is what you’re dealing with. You can separate the thermostat from its base and supply power by using a USB cable. If it displays error code 195, you should continue to visually check components like the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to uncover anything wrong with these components, it will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than needed. This can stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. The technician should carefully examine and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it might still keep you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting sufficient 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 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 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 excessive power is sent through 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 shut the power off as soon as possible. You can then get a hold of a professional technician with the appropriate experience detecting and fixing electrical issues.

e73 – Critical

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

This will sometimes be as easy as the breaker being shut off, but it could also be an issue with the wiring. After switching 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 looks to be out of place, it’s best to get in touch with a local professional.