Operating a Nest thermostat is one of the easiest 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 properly 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 professional technician can use to provide solutions that much faster.

Listed below are seven of the most frequent error codes you could discover on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you might address it and the approximate cost to do so. Remember that while the investment will ultimately depend on the precise Nest model, you can expect to pay about $75-$200 for repairs. This should include travel and labor costs along with any specific parts needed to complete repairs.

e298 – Critical

This critical error code is limited to the latest 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 change to the backup battery system. The error message will continue to be displayed until the problem is dealt with.

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

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first perform a factory reset of your thermostat to ensure it’s not merely a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.

They’ll disconnect the power and progressively check each wire, seeing to it that they are fully inserted into the connector with the correct amount of exposed copper. After they find the malfunctioning connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can shut down and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will eventually turn off. Presuming the breakers are on, you can check a few other places before consulting a professional technician.

As this error can consume your thermostat’s battery, the first step might be supplying enough power to figure out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and supply power with a USB cable. Assuming it reveals error code 195, you can continue to visually examine components like 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 signifies an electrical issue with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than needed. This may stem from the breaker box, an error from the control board or thanks to a faulty connection in the thermostat. The technician needs to meticulously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

While 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 the absence of one can block your Nest from getting adequate power. You can inspect the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you can get a Nest Power Connector.

Due to installation of a Nest Power Connector, you will sometimes notice error code E297 show up. 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 that’s the result of an overcurrent. If excess power is being delivered using the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to guard against electrical damage, it’s a good idea to shut the power off straightaway. You can then contact a professional technician with the appropriate experience detecting and resolving electrical damage.

e73 – Critical

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

This may be as easy as the breaker being turned 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 they’re not loose or damaged. If nothing seems to be out of place, it’s time to speak with a local professional.