Using a Nest thermostat is one of the easiest ways to optimize the everyday schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make adjustments. But as you might expect, it won’t work well or at all if you see an error code show up. The specific error code provides useful information about the root of the problem, something a trained technician can use to offer solutions that much quicker.

Here are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll explain the basics of each error code along with how you might fix it and the estimated cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can anticipate paying between $75-$200 for repairs. This should include things like travel and labor costs as well as any specific hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed 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 resolved.

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

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start checking connectors.

They’ll detach the power and slowly look at each wire, ensuring they are fully inserted into the connector with the proper amount of bare copper. When they locate 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 sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will finally power down. In the event the breakers are on, you can check a couple of other places before calling a professional technician.

Since this error can consume your thermostat’s battery, the first step could be supplying enough power to find out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and deliver power through a USB cable. Assuming it displays error code 195, you may continue to visually check components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can’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 suggests 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 will sometimes stem from the breaker box, an error from the control board or through a bad connection in the thermostat. A technician can carefully inspect and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it can still keep you from using the Nest thermostat how you prefer to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining adequate power. You can examine the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you can get a Nest Power Connector.

With installation of a Nest Power Connector, you might 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 be required 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 originating from an overcurrent. If excess power is transported inside the Nest’s wiring, it can damage internal components and could even be a fire hazard. If you see this error code appear on your Nest thermostat and want to guard against electrical damage, it’s a good idea to turn the power off as soon as possible. You can then get a hold of a professional technician with the appropriate experience diagnosing and solving electrical problems.

e73 – Critical

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

This may be as straightforward as the breaker being shut off, but it may also be something with the wiring. After turning 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 time to speak with a local professional.