Operating a Nest thermostat is one of the easiest ways to improve the day-to-day schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make improvements. But as you can expect, it won’t work correctly or at all if you see an error code on the display. The specific error code supplies useful information about the root of the problem, something a professional technician can use to present solutions that much faster.

Let’s consider seven of the most frequent error codes you might encounter on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you might address it and the approximate cost to do so. Remember that while the costs will ultimately be dependent on the exact Nest model, you can count on paying about $75-$200 for repairs. This should include travel and labor costs as well as any specific hardware needed to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest 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 continue to be displayed until the problem is dealt with.

Losing power to your Nest thermostat can be for numerous reasons. The wiring could have disconnected or become damaged, or a disconnection might have appeared further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A knowledgeable technician will check 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 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 make sure it’s not merely a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin looking at connectors.

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

e195 – Critical

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

Because this error can drain your thermostat’s battery, the first step may be restoring enough power to figure out if this specific error code is what you’re facing. You can disconnect the thermostat from its base and supply 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 can’t detect anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical issue with your Nest thermostat. More specifically, e103 may 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 through a bad connection in the thermostat. A technician can carefully examine and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Although this error code isn’t critical, it may still keep you from using the Nest thermostat how you prefer to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from receiving enough power. You can check 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 will sometimes notice error code E297 appear. 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

Just like error code e103, e104 is a critical error stemming from an overcurrent. If excess power is being delivered inside the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to shut the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience diagnosing and solving 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 easy 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 appears to be out of place, it’s best to get in touch with a local professional.