Operating a Nest thermostat is one of the easiest ways to optimize the daily schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make adjustments. But as you may expect, it won’t work correctly or at all if you see an error code show up. The specific error code provides useful information about the underlying problem, something a professional technician can use to offer solutions that much sooner.

Let’s consider seven of the most frequent error codes you may encounter on your Nest thermostat. We’ll explain the basics of each error code on top of how you could solve it and the projected cost to do so. Don’t forget that while the investment will ultimately be dependent on the precise Nest model, you can expect to pay about $75-$200 for repairs. This should include things like travel and labor costs as well as any specific components required to wrap up 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. Because 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 fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection may have occurred further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will inspect 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 perform a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and gradually look at each wire, seeing to it that they are fully placed into the connector with the correct amount of uncovered copper. After they pinpoint the malfunctioning connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly hot. The HVAC system can break down and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will finally power down. Presuming the breakers are on, you can search a few other places before consulting a professional technician.

As this error can deplete your thermostat’s battery, the first step could be providing enough power to find out if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and provide power through a USB cable. In the event it reveals error code 195, you should continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This may stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. Your technician will carefully investigate and test the Nest’s electrical system to determine 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 the absence of one can block your Nest from receiving 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’ll need a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead have 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 excess power is transported inside the Nest’s wiring, it may damage internal components and may even be a fire hazard. If you notice this error code pop up 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 diagnosing and resolving electrical issues.

e73 – Critical

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

This could be as straightforward as the breaker being turned off, but it may 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 looks to be out of place, it’s time to get in touch with a local professional.