Using a Nest thermostat is one of the easiest ways to perfect the daily schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code show up. The exact error code supplies useful information about the source of the problem, something a trained technician can use to present solutions that much sooner.

Let’s consider seven of the most likely error codes you might find on your Nest thermostat. We’ll review the basics of each error code along with how you can fix it and the approximate cost to do so. Don’t forget that while the costs will ultimately be dependent on the specific Nest model, you can expect to pay about $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware necessary 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 shut off. As this is a critical power error, the thermostat will switch to the backup battery system. The error message will continue to be displayed until the issue is resolved.

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 professional technician should inspect electrical connections and wiring until they uncover the source of the problem.

e294 – Critical

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

They’ll detach the power and slowly check each wire, making sure they are fully inserted into the connector with the correct amount of bare copper. After they find the malfunctioning connector, it can be exchanged 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 subsequently shut down. Assuming the breakers are on, you can check a few other places before calling a professional technician.

Because this error can deplete your thermostat’s battery, the first step might be providing enough power to determine if this specific error code is what you’re dealing with. You can separate 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 check components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can’t find anything wrong with these components, it’s maybe best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical malfunction with your Nest thermostat. More specifically, e103 can 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 through a faulty connection in the thermostat. Your technician can meticulously examine and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it might 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 can get a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead need 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 too much power is transported through the Nest’s wiring, it could 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 a good idea to shut the power off straightaway. You can then contact a professional technician with the appropriate experience diagnosing 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 easy as the breaker being shut off, but it can also be something with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure nothing is loose or damaged. If nothing looks to be out of place, it’s time to contact a local professional.