Here's What These 7 Nest Thermostat Error Codes Mean

Operating a Nest thermostat is one of the easiest ways to optimize the everyday schedule of your comfort system. This smart thermostat can learn your preferences and automatically make improvements. But as you might expect, it won’t work properly or at all if you see an error code appear. The exact error code provides useful information about the root of the problem, something a professional technician can use to present solutions that much sooner.

Let’s consider seven of the most frequent error codes you might encounter on your Nest thermostat. We’ll explain the basics of each error code along with how you could fix it and the estimated cost to do so. Don’t forget that while the costs will ultimately depend on the precise Nest model, you can expect to pay between $75-$200 for repairs. This should include things like travel and labor costs as well as any specific components necessary to finish repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and is displayed when the power is shut off. As this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on the screen 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 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 locate the root 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 perform 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 inspecting connectors.

They’ll shut off the power and progressively inspect each wire, ensuring they are fully attached into the connector with the correct amount of bare copper. When they find the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can show up when the weather outside is particularly hot. The HVAC system can shut down and stop giving power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will eventually power down. Presuming the breakers are on, you can check a few other places before consulting a professional technician.

Because this error can drain your thermostat’s battery, the first step might be providing enough power to figure out if this specific error code is what you’re working with. You can disconnect the thermostat from its base and deliver power with a USB cable. In the event it displays error code 195, you can continue to visually check components like the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to detect anything wrong with these components, it’s maybe best to get in touch with 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 receiving more power than what is safe and normal. This can stem from the breaker box, an error from the control board or through a bad connection in the thermostat. A technician needs to meticulously inspect 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

Even though this error code isn’t critical, it can still stop 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 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.

Due to installation of a Nest Power Connector, you might notice error code E297 show up. This can be dealt with 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

Like error code e103, e104 is a critical error stemming from an overcurrent. If too much power is sent inside the Nest’s wiring, it may damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to protect from electrical damage, it’s a good idea to turn the power off as soon as you can. You can then get in touch with a professional technician with the appropriate experience diagnosing and resolving electrical damage.

e73 – Critical

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

This could be as simple as the breaker being turned off, but it can also be an issue with the wiring. After turning 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 contact a local professional.