Operating a Nest thermostat is one of the best ways to perfect the daily schedule of your HVAC system. This smart thermostat can learn 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 precise error code supplies useful information about the root of the problem, something a trained technician can use to provide solutions that much sooner.

Here are seven of the most likely error codes you might find on your Nest thermostat. We’ll review the basics of each error code as well as how you can fix it and the estimated cost to do so. Don’t forget that while the price will ultimately hinge 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 parts required to complete repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and appears when the power is disconnected from the system. Because 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 dealt with.

Losing power to your Nest thermostat can be for several reasons. The wiring may 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 should check electrical connections and wiring until they uncover 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 should reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not merely a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start inspecting connectors.

They’ll shut off the power and progressively check each wire, seeing to it that they are fully inserted into the connector with the proper amount of exposed copper. Once they find the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely 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 finally power down. Presuming the breakers are on, you can check a few other places before calling a professional technician.

As this error can drain your thermostat’s battery, the first step could be supplying enough power to determine if this specific error code is what you’re facing. You can disconnect the thermostat from its base and provide power through a USB cable. In the event it presents error code 195, you can 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’s maybe best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical error with your Nest thermostat. More specifically, e103 will 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 thanks to a defective connection in the thermostat. The technician will cautiously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Although this error code isn’t critical, it could 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 receiving sufficient 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 can get a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector is 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 inside the Nest’s wiring, it may damage internal components and may 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 shut the power off straightaway. You can then contact a professional technician with the appropriate experience identifying and fixing electrical issues.

e73 – Critical

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

This could be as simple as the breaker being switched off, but it can also be a problem with the wiring. After turning 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 seems to be out of place, it’s time to contact a local professional.