Installing a Nest thermostat is one of the best ways to improve the everyday schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make improvements. But as you might expect, it won’t work well or at all if you see an error code on the display. The precise error code provides useful information about the root of the problem, something a professional technician can use to offer solutions that much quicker.

Listed below are seven of the most likely error codes you may encounter on your Nest thermostat. We’ll explain the basics of each error code along with how you could fix it and the projected cost to do so. Keep in mind that while the price will ultimately hinge on the precise Nest model, you can count on paying about $75-$200 for repairs. This should include things like travel and labor costs on top of any specific parts required 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. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will continue to be displayed until the problem is resolved.

Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection may have occurred further along in the electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician should inspect 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, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software problem. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin looking at connectors.

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

e195 – Critical

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

As this error can deplete your thermostat’s battery, the first step may be supplying enough power to determine if this specific error code is what you’re dealing with. You can separate the thermostat from its base and provide power with a USB cable. Assuming it presents error code 195, you should continue to visually inspect components such as 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 probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical malfunction with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than needed. This will sometimes stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. Your technician needs to meticulously examine and test the Nest’s electrical system to determine 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 can still stop you from using the Nest thermostat how you prefer to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from receiving sufficient power. You can inspect the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you need a Nest Power Connector.

With installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be dealt with 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 originating from an overcurrent. If too much power is sent through the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you see this error code appear on your Nest thermostat and want to protect from electrical damage, it’s a good idea to shut the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience identifying and solving 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 straightforward as the breaker being switched off, but it may also be a problem with the wiring. After turning 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 time to contact a local professional.