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

Listed below are seven of the most common error codes you could find on your Nest thermostat. We’ll review the basics of each error code along with how you might address it and the approximate cost to do so. Remember that while the costs will ultimately depend on the exact Nest model, you can count on paying around $75-$200 for repairs. This should include things like travel and labor costs as well as any specific hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and shows up 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 remain on the screen until the problem is dealt with.

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

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring has 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 simply a software issue. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and gradually check each wire, seeing to it that they are fully inserted into the connector with the correct amount of exposed copper. After they pinpoint the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can show up when the weather outside is especially hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will eventually shut down. Presuming the breakers are on, you can inspect a handful of other places before calling a professional technician.

Because this error can deplete your thermostat’s battery, the first step may be providing enough power to find out if this specific error code is what you’re working with. You can separate the thermostat from its base and deliver power with a USB cable. Assuming it displays error code 195, you may continue to visually inspect components such as 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 will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than what is safe and normal. This can stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. The technician can cautiously investigate 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

Even though this error code isn’t critical, it could still keep 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 check the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you’ll need a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 appear. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already 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 originating from an overcurrent. If too much power is sent using the Nest’s wiring, it can damage internal components and can 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 recommended to switch the power off as soon as you can. You can then contact a professional technician with the proper experience detecting and fixing electrical problems.

e73 – Critical

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

This might be as simple as the breaker being switched off, but it could also be a problem with the wiring. After switching 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 best to get in touch with a local professional.