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 adjustments. But as you can expect, it won’t work correctly or at all if you see an error code show up. The exact error code provides useful information about the root of the problem, something a professional technician can use to provide solutions that much faster.

Listed below are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll explain the basics of each error code on top of how you might address it and the projected cost to do so. Don’t forget that while the investment will ultimately be dependent on the exact Nest model, you can expect to pay around $75-$200 for repairs. This should also cover travel and labor costs along with any specific hardware required to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears 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 display 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 occurred further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician should 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 should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start checking connectors.

They’ll detach the power and progressively inspect each wire, seeing to it that they are fully placed into the connector with the proper amount of uncovered copper. After they locate the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can show up when the weather outside is especially hot. The HVAC system can shut down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally power down. In the event the breakers are on, you can inspect a few other places before contacting a professional technician.

Since this error can deplete 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 separate 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 inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to uncover 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 can refer to an overcurrent problem, which means the wiring is receiving more power than needed. This may stem from the breaker box, an error from the control board or through a bad connection in the thermostat. A technician should meticulously inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it can still stop you from using the Nest thermostat how you want 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 obtaining sufficient 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 can get a Nest Power Connector.

With installation of a Nest Power Connector, you will sometimes notice error code E297 show up. 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

Similar to error code e103, e104 is a critical error that’s the result of an overcurrent. If excess power is sent through the Nest’s wiring, it could damage internal components and could 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 shut the power off as soon as possible. You can then get a hold of a professional technician with the appropriate experience identifying and fixing electrical issues.

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 can also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing looks to be out of place, it’s time to speak with a local professional.