Using a Nest thermostat is one of the best ways to optimize the daily schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make adjustments. But as you can expect, it won’t work properly or at all if you see an error code appear. The specific error code offers 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 likely error codes you might discover on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can fix it and the approximate cost to do so. Remember that while the costs will ultimately hinge on the exact Nest model, you can count on paying about $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 the latest models of the Nest thermostat and appears when the power is detached from the system. As 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 fixed.

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

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to ensure it’s not just a software problem. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and slowly look at each wire, ensuring they are fully placed into the connector with the correct amount of uncovered copper. After they find the damaged 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 fail and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will finally turn off. In the event the breakers are on, you can search a few other places before consulting a professional technician.

As this error can drain your thermostat’s battery, the first step might be providing enough power to figure out if this specific error code is what you’re working with. You can disconnect the thermostat from its base and supply power through a USB cable. Assuming it displays error code 195, you should continue to visually examine components like 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’s maybe best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical error with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than needed. This may stem from the breaker box, an error from the control board or through a faulty connection in the thermostat. A technician can cautiously 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 might still stop you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from obtaining adequate power. You can examine the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you need a Nest Power Connector.

Due to installation of a Nest Power Connector, you will sometimes notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 stemming from an overcurrent. If too much power is transported inside the Nest’s wiring, it could damage internal components and may even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to shut the power off as soon as you can. You can then get a hold of a professional technician with the proper experience identifying and fixing electrical issues.

e73 – Critical

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

This could be as easy as the breaker being switched off, but it could also be a problem with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing seems to be out of place, it’s time to get in touch with a local professional.