Operating a Nest thermostat is one of the most convenient ways to optimize the day-to-day schedule of your comfort system. This smart thermostat can recognize 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 appear. The precise error code offers useful information about the root of the problem, something a trained technician can use to present solutions that much faster.

Let’s consider seven of the most likely error codes you might find on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you could solve it and the estimated cost to do so. Don’t forget that while the investment will ultimately be dependent on the exact Nest model, you can anticipate paying around $75-$200 for repairs. This should also cover travel and labor costs as well as any specific parts necessary to finish repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and is displayed 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 fixed.

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

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should 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 merely a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start looking at connectors.

They’ll disconnect the power and slowly check each wire, seeing to it that they are fully placed into the connector with the proper amount of uncovered copper. Once they pinpoint the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is severely hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will subsequently shut down. In the event the breakers are on, you can inspect a few other places before contacting a professional technician.

Because this error can deplete your thermostat’s battery, the first step could be supplying 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 deliver power with a USB cable. In the event it reveals error code 195, you can continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to detect anything wrong with these components, it’s maybe best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical error with your Nest thermostat. More specifically, e103 will 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 thanks to a faulty connection in the thermostat. Your technician needs to carefully inspect and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it may still stop you from using the Nest thermostat how you want to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining adequate 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’ll need a Nest Power Connector.

During installation of a Nest Power Connector, you may notice error code E297 show up. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 that’s the result of an overcurrent. If excessive power is sent 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 take steps to prevent electrical damage, it’s a good idea to turn the power off straightaway. You can then get in touch with a professional technician with the proper experience detecting and fixing electrical issues.

e73 – Critical

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

This might be as straightforward as the breaker being turned off, but it can also be a problem with the wiring. After turning off the power to your HVAC system and thermostat, you can visually examine the wires to make sure nothing is loose or damaged. If nothing appears to be out of place, it’s time to get in touch with a local professional.