Installing a Nest thermostat is one of the most convenient ways to improve the daily schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make adjustments. But as you might expect, it won’t work well or at all if you see an error code appear. The specific error code offers useful information about the root of the problem, something a professional technician can use to provide solutions that much quicker.

Let’s consider seven of the most likely error codes you may encounter on your Nest thermostat. We’ll review the basics of each error code as well as how you can address it and the approximate cost to do so. Don’t forget that while the costs will ultimately hinge on the precise Nest model, you can expect to pay around $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware necessary to complete repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is shut off. Since this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on display until the problem is dealt with.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection could have happened further along in your electrical system. This may 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 shows up when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first complete 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 begin inspecting connectors.

They’ll detach the power and gradually look at each wire, making sure they are fully attached into the connector with the proper amount of bare copper. When they find the malfunctioning connector, it can be replaced for a new one.

e195 – Critical

This critical error code can surface 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 depletes and the thermostat will subsequently shut down. In the event the breakers are on, you can inspect a handful of other places before contacting a professional technician.

Since this error can consume your thermostat’s battery, the first step may be restoring enough power to figure out if this specific error code is what you’re working with. You can detach the thermostat from its base and deliver power through a USB cable. If 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 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 issue with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This can stem from the breaker box, an error from the control board or through a defective connection in the thermostat. Your technician will carefully examine 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

Although this error code isn’t critical, it can 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 not having one can block your Nest from getting 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’ll need a Nest Power Connector.

With installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be resolved 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 stemming from an overcurrent. If excessive power is sent inside the Nest’s wiring, it could damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience diagnosing and fixing electrical damage.

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 shut off, but it could also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually examine the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s best to speak with a local professional.