Installing a Nest thermostat is one of the best ways to perfect the daily schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make improvements. But as you can expect, it won’t work properly or at all if you see an error code show up. The exact error code provides useful information about the source of the problem, something a knowledgeable technician can use to present solutions that much quicker.

Here are 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 address it and the projected cost to do so. Keep in mind that while the price will ultimately depend on the exact Nest model, you can expect to pay around $75-$200 for repairs. This should include travel and labor costs as well as any specific components 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. 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 fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection might have appeared further along in the electrical system. This might 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 appears when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first perform a factory reset of your thermostat to ensure it’s not simply a software issue. 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 inspect each wire, making sure they are fully attached into the connector with the proper amount of bare copper. After they find the malfunctioning connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is especially hot. The HVAC system can shut down and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will finally power down. In the event the breakers are on, you can check a couple of other places before consulting a professional technician.

Because this error can consume your thermostat’s battery, the first step might be restoring enough power to figure out if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and deliver power through a USB cable. Assuming it displays error code 195, you should continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t uncover anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 signifies 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 can stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. A technician can meticulously examine 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

Even though this error code isn’t critical, it may 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 not having one can block your Nest from getting 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 can get 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 was already 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 that’s the result of an overcurrent. If excessive power is sent using the Nest’s wiring, it can 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 protect from electrical damage, it’s a good idea to switch the power off straightaway. You can then get in touch with a professional technician with the proper experience identifying and fixing electrical malfunctions.

e73 – Critical

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

This will sometimes be as easy as the breaker being shut 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 nothing is loose or damaged. If nothing seems to be out of place, it’s time to get in touch with a local professional.