Operating a Nest thermostat is one of the most convenient ways to optimize the daily schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make changes. But as you might expect, it won’t work correctly or at all if you see an error code show up. The precise error code provides useful information about the underlying problem, something a trained technician can use to provide solutions that much faster.

Let’s consider seven of the most common error codes you could discover on your Nest thermostat. We’ll review the basics of each error code along with how you can address it and the projected cost to do so. Remember that while the investment will ultimately be dependent on the specific Nest model, you can count on paying around $75-$200 for repairs. This should include travel and labor costs along with any specific components 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 shut off. Because this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on the screen until the issue is fixed.

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 happened further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician will inspect 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 needs to be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first perform a factory reset of your thermostat to make sure it’s not simply a software issue. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin checking connectors.

They’ll detach the power and gradually inspect each wire, ensuring they are fully inserted into the connector with the correct amount of uncovered copper. When they find the problem connector, it can be replaced for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly hot. The HVAC system can fail and stop sending power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will subsequently shut down. Assuming the breakers are on, you can check a handful of other places before contacting a professional technician.

Because this error can deplete your thermostat’s battery, the first step could be supplying enough power to figure out if this specific error code is what you’re working with. You can detach the thermostat from its base and supply power through a USB cable. Assuming it presents error code 195, you may continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it will likely be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical malfunction with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This may stem from the breaker box, an error from the control board or through a defective connection in the thermostat. A technician should meticulously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

Although this error code isn’t critical, it might still keep you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining enough power. You can check the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you’ll need a Nest Power Connector.

Due to 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 was 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 that’s the result of an overcurrent. If excessive power is being delivered inside the Nest’s wiring, it could damage internal components and can 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 recommended to shut the power off as soon as you can. You can then contact a professional technician with the appropriate experience detecting and fixing electrical damage.

e73 – Critical

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

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