How to Resolve These Seven Error Codes on Your Nest Thermostat

Operating a Nest thermostat is one of the best ways to optimize the daily schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make changes. But as you can expect, it won’t work well or at all if you see an error code on the display. The exact error code offers useful information about the underlying problem, something a professional technician can use to present solutions that much quicker.

Let’s consider seven of the most likely error codes you might encounter on your Nest thermostat. We’ll explain the basics of each error code as well as how you can address it and the approximate cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can anticipate paying around $75-$200 for repairs. This should also cover travel and labor costs along with any specific hardware required to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is shut off. Because this is a critical power error, the thermostat will change to the backup battery system. The error message will continue to be displayed until the problem is resolved.

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

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to 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 examine the wiring diagram of the thermostat and start checking connectors.

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

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can fail 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. In the event the breakers are on, you can examine a couple of other places before consulting a professional technician.

As this error can drain your thermostat’s battery, the first step could be providing 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 deliver power through a USB cable. Assuming it reveals error code 195, you may 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 get in touch with a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is getting more power than necessary. This may stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. Your technician needs to cautiously investigate 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

Although this error code isn’t critical, it could 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 enough 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’ll need a Nest Power Connector.

With installation of a Nest Power Connector, you might notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector is 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 too much power is transported inside the Nest’s wiring, it may damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s suggested to shut the power off as soon as you can. You can then get in touch with a professional technician with the proper experience identifying and solving electrical malfunctions.

e73 – Critical

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

This may be as easy as the breaker being shut off, but it can 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 nothing is loose or damaged. If nothing appears to be out of place, it’s best to contact a local professional.