Installing a Nest thermostat is one of the best ways to perfect the day-to-day schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make improvements. But as you may expect, it won’t work correctly or at all if you see an error code on the display. The precise error code supplies useful information about the underlying problem, something a knowledgeable technician can use to provide solutions that much sooner.

Here are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll walk you through the basics of each error code along with how you could solve it and the estimated cost to do so. Keep in mind that while the costs will ultimately be dependent on the exact Nest model, you can count on paying around $75-$200 for repairs. This should include travel and labor costs on top of any specific parts needed to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears when the power is detached 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 issue is dealt with.

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

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring has 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 just a software error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin inspecting connectors.

They’ll shut off the power and slowly inspect each wire, seeing to it that they are fully placed into the connector with the proper amount of uncovered copper. When they locate the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally power down. Assuming the breakers are on, you can examine a handful of other places before calling a professional technician.

As this error can drain your thermostat’s battery, the first step may be supplying enough power to determine if this specific error code is what you’re working with. You can detach the thermostat from its base and deliver power by using a USB cable. Assuming it presents error code 195, you can continue to visually check components like the wiring as well as your air conditioner’s air filter or drainage system. If you can’t uncover 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 problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is getting more power than necessary. This may stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. The technician should meticulously examine 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 might 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 not having one can block your Nest from getting enough 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’ll need a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead have to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Like error code e103, e104 is a critical error originating from an overcurrent. If excess 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 take steps to prevent electrical damage, it’s a good idea to switch the power off as soon as you can. You can then get a hold of a professional technician with the proper experience detecting and resolving electrical issues.

e73 – Critical

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

This will sometimes be as simple as the breaker being turned off, but it may also be something with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s time to get in touch with a local professional.