Operating a Nest thermostat is one of the easiest ways to improve the day-to-day schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make improvements. But as you may expect, it won’t work well or at all if you see an error code appear. The specific error code provides useful information about the underlying problem, something a trained technician can use to offer solutions that much faster.

Let’s consider seven of the most common error codes you may encounter on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can fix it and the projected cost to do so. Don’t forget that while the costs will ultimately hinge on the specific Nest model, you can count on paying between $75-$200 for repairs. This should also cover travel and labor costs as well as any specific hardware required to complete repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed when the power is detached from the system. Because this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on display until the problem is resolved.

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

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software problem. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin checking connectors.

They’ll disconnect the power and gradually look at each wire, seeing to it that they are fully placed into the connector with the proper amount of exposed copper. After they locate the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will subsequently power down. Presuming the breakers are on, you can search a handful of other places before calling a professional technician.

Since this error can deplete your thermostat’s battery, the first step could be restoring enough power to figure out if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and supply power by using a USB cable. Assuming it reveals error code 195, you can continue to visually examine components such as the wiring as well as your air conditioner’s air filter or drainage system. If you don’t uncover anything wrong with these components, it’s maybe 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 faulty connection in the thermostat. Your technician can cautiously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it can still prevent 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 missing one can block your Nest from obtaining adequate power. You can examine 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 might notice error code E297 be displayed. This can be dealt with 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

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 can even be a fire hazard. If you notice this error code appear 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 possible. You can then get in touch with a professional technician with the proper experience detecting and fixing electrical damage.

e73 – Critical

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

This may be as straightforward as the breaker being turned off, but it can also be something with the wiring. After turning off the power to your HVAC system and thermostat, you can visually examine the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s a good idea to speak with a local professional.