Installing a Nest thermostat is one of the most convenient ways to perfect the everyday schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make improvements. But as you might expect, it won’t work properly or at all if you see an error code on the display. The exact error code supplies useful information about the source of the problem, something a professional technician can use to present solutions that much quicker.

Here are seven of the most common error codes you could encounter on your Nest thermostat. We’ll review the basics of each error code on top of how you could solve it and the approximate cost to do so. Remember that while the investment will ultimately depend on the precise Nest model, you can expect to pay between $75-$200 for repairs. This should include things like travel and labor costs along with any specific parts necessary to wrap up repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and appears when the power is shut off. Since this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on the screen until the issue is fixed.

Losing power to your Nest thermostat can be for a number of reasons. The wiring may have disconnected or become damaged, or a disconnection might have happened further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A professional technician should 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 should be reconfigured. More specifically, you’ll need the technician 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 check the wiring diagram of the thermostat and begin inspecting connectors.

They’ll detach the power and progressively inspect each wire, making sure they are fully attached into the connector with the proper amount of uncovered copper. When they find the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is particularly hot. The HVAC system can shut down and stop delivering 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 handful of other places before calling a professional technician.

Because this error can deplete your thermostat’s battery, the first step may be restoring enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and supply power by using a USB cable. Assuming it reveals error code 195, you may continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t find anything wrong with these components, it will probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is getting more power than needed. This will sometimes stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. The technician needs to cautiously investigate 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

Even though this error code isn’t critical, it may still keep you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from getting adequate 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 need a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 being delivered through the Nest’s wiring, it can damage internal components and could even be a fire hazard. If you see this error code appear on your Nest thermostat and want to protect from electrical damage, it’s recommended to turn the power off straightaway. You can then get a hold of a professional technician with the necessary experience identifying and solving electrical problems.

e73 – Critical

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

This might be as straightforward as the breaker being turned off, but it can also be something with the wiring. After switching off the power to your HVAC system and thermostat, you can visually check the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s time to get in touch with a local professional.