Installing a Nest thermostat is one of the best ways to improve the everyday schedule of your comfort system. This smart thermostat can learn 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 show up. The precise error code offers useful information about the root of the problem, something a trained technician can use to present solutions that much faster.

Listed below are seven of the most likely error codes you may find on your Nest thermostat. We’ll review the basics of each error code along with how you could address it and the estimated cost to do so. Don’t forget that while the costs will ultimately depend on the specific Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts necessary to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is disconnected from the system. Because this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on display until the problem 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 occurred further along in your home’s electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician can examine electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring has to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin inspecting connectors.

They’ll detach the power and slowly check each wire, making sure they are fully attached into the connector with the proper amount of bare copper. Once they pinpoint the malfunctioning connector, it can be replaced for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will subsequently shut down. Assuming the breakers are on, you can inspect a few other places before calling a professional technician.

Since 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 detach the thermostat from its base and supply power with a USB cable. In the event it displays error code 195, you should continue to visually inspect 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 call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical malfunction with your Nest thermostat. More specifically, e103 will 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 defective connection in the thermostat. A technician will cautiously inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

While this error code isn’t critical, it might still prevent you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting enough 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.

With installation of a Nest Power Connector, you will sometimes 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

Like error code e103, e104 is a critical error originating from an overcurrent. If too much power is being delivered using the Nest’s wiring, it can damage internal components and can 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 suggested to turn the power off as soon as you can. You can then get a hold of a professional technician with the proper experience identifying and fixing electrical malfunctions.

e73 – Critical

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

This will sometimes be as easy as the breaker being switched off, but it could also be a problem 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 appears to be out of place, it’s time to get in touch with a local professional.