Installing a Nest thermostat is one of the most convenient ways to improve the day-to-day schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make improvements. But as you can expect, it won’t work well or at all if you see an error code on the display. The specific error code provides useful information about the root of the problem, something a knowledgeable technician can use to offer solutions that much quicker.

Here are seven of the most common error codes you may encounter on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you might solve it and the estimated cost to do so. Keep in mind that while the price will ultimately depend on the specific Nest model, you can expect to pay around $75-$200 for repairs. This should also cover travel and labor costs on top of any specific hardware needed to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed when the power is disconnected from the system. Since 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 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 appeared further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician will inspect electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring should 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 merely a software problem. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin inspecting connectors.

They’ll disconnect 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. After they find the problem connector, it can be replaced for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can break down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will subsequently turn off. Assuming the breakers are on, you can check a handful of other places before calling a professional technician.

Because this error can deplete your thermostat’s battery, the first step might be providing enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and provide power by using a USB cable. In the event it reveals error code 195, you can continue to visually examine components including 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 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 can refer to an overcurrent problem, which means the wiring is experiencing more power than what is safe and normal. This may stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. A technician should carefully investigate and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it may still prevent 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 the absence of one can block your Nest from getting adequate power. You can check 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.

With installation of a Nest Power Connector, you might notice error code E297 appear. 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

Just 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 can damage internal components and could 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 switch the power off as soon as you can. You can then contact a professional technician with the appropriate experience identifying and solving electrical malfunctions.

e73 – Critical

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

This might be as simple as the breaker being turned off, but it can also be something with the wiring. After shutting 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 seems to be out of place, it’s best to contact a local professional.