Here's What These 7 Nest Thermostat Error Codes Mean

Operating a Nest thermostat is one of the easiest ways to perfect the day-to-day schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make adjustments. 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 provides useful information about the root of the problem, something a professional technician can use to present solutions that much faster.

Listed below are seven of the most frequent error codes you could discover on your Nest thermostat. We’ll explain the basics of each error code along with how you might solve it and the approximate cost to do so. Don’t forget that while the costs will ultimately depend on the precise Nest model, you can count on paying about $75-$200 for repairs. This should include things like travel and labor costs along with any specific components necessary to wrap up repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and is displayed when the power is disconnected from the system. As this is a critical power error, the thermostat will swap 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 a number of reasons. The wiring may have disconnected or become damaged, or a disconnection may have appeared further along in your home’s electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will inspect electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to ensure it’s not just a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin inspecting connectors.

They’ll disconnect the power and gradually look at each wire, ensuring they are fully inserted into the connector with the correct amount of exposed copper. Once they find the problem connector, it can be swapped for a new one.

e195 – Critical

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

Since this error can drain your thermostat’s battery, the first step may 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 deliver power through a USB cable. Assuming it presents error code 195, you may continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you can’t uncover 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 experiencing more power than needed. This will sometimes stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. The technician can meticulously inspect 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

While this error code isn’t critical, it might still prevent you from using the Nest thermostat how you want to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining adequate 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.

Due to installation of a Nest Power Connector, you will sometimes notice error code E297 be displayed. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 that’s the result of an overcurrent. If excessive 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 show up on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to switch the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience diagnosing and resolving electrical malfunctions.

e73 – Critical

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

This may be as easy as the breaker being turned off, but it can also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually examine the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s best to contact a local professional.