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

Listed below are seven of the most likely error codes you may find on your Nest thermostat. We’ll walk you through the basics of each error code along with how you could address it and the projected cost to do so. Remember that while the price will ultimately hinge on the exact Nest model, you can expect to pay about $75-$200 for repairs. This should also cover travel and labor costs along with any specific components needed to complete repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is detached from the system. 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 resolved.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection might have happened further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician should check electrical connections and wiring until they uncover the source of the problem.

e294 – Critical

Critical error code e294 is displayed 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 make sure it’s not just a software problem. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.

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

e195 – Critical

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

Because this error can deplete your thermostat’s battery, the first step may 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 supply power by using a USB cable. If it presents error code 195, you may continue to visually check components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to 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 problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than needed. This may stem from the breaker box, an error from the control board or through a bad connection in the thermostat. The technician needs to carefully examine and test the Nest’s electrical system to understand where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

While this error code isn’t critical, it could still prevent 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 getting enough power. You can inspect 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.

Due to installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be resolved 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

Similar to error code e103, e104 is a critical error stemming from an overcurrent. If excess power is transported using the Nest’s wiring, it may damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s suggested to shut the power off as soon as possible. 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 will sometimes be as easy as the breaker being shut off, but it can also be an issue with the wiring. After switching off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s a good idea to get in touch with a local professional.