Installing a Nest thermostat is one of the most convenient ways to improve the everyday schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make changes. But as you may expect, it won’t work correctly or at all if you see an error code on the display. The precise error code offers useful information about the underlying problem, something a professional technician can use to provide solutions that much sooner.

Let’s consider seven of the most common error codes you might encounter on your Nest thermostat. We’ll review the basics of each error code as well as how you could address 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 between $75-$200 for repairs. This should include things like travel and labor costs on top of any specific components needed to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is detached from the system. As this is a critical power error, the thermostat will swap to the backup battery system. The error message will continue to be displayed until the issue is fixed.

Losing power to your Nest thermostat can be for numerous 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 should inspect electrical connections and wiring until they find the source of the problem.

e294 – Critical

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

They’ll shut off the power and progressively inspect each wire, ensuring they are fully attached into the connector with the correct 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 show up when the weather outside is severely hot. The HVAC system can shut down and stop sending power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally power down. Assuming the breakers are on, you can examine a couple of other places before contacting a professional technician.

Since this error can consume your thermostat’s battery, the first step might be restoring enough power to determine if this specific error code is what you’re working with. You can separate the thermostat from its base and supply power with a USB cable. If it reveals error code 195, you may continue to visually check components including 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 will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This will sometimes stem from the breaker box, an error from the control board or through a faulty connection in the thermostat. The technician can meticulously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat believes 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 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from receiving sufficient 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.

Due to installation of a Nest Power Connector, you may 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

Similar to error code e103, e104 is a critical error originating from an overcurrent. If too much power is being delivered inside the Nest’s wiring, it can damage internal components and could even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s a good idea to switch the power off straightaway. You can then get in touch with a professional technician with the proper experience diagnosing and solving electrical problems.

e73 – Critical

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

This will sometimes be as straightforward as the breaker being switched off, but it can also be something with the wiring. After switching 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 looks to be out of place, it’s time to get in touch with a local professional.