Installing a Nest thermostat is one of the best ways to perfect the everyday schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make adjustments. But as you might expect, it won’t work properly or at all if you see an error code on the display. The precise error code supplies useful information about the underlying problem, something a knowledgeable technician can use to provide solutions that much quicker.
Listed below are seven of the most frequent error codes you might find on your Nest thermostat. We’ll explain the basics of each error code on top of how you might address it and the estimated cost to do so. Keep in mind that while the costs will ultimately be dependent on the precise Nest model, you can count on paying between $75-$200 for repairs. This should also cover travel and labor costs on top of any specific components required to finish repairs.
e298 - Critical
This critical error code is limited to newer models of the Nest thermostat and shows up when the power is disconnected from the system. Since this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on display until the issue is dealt with.
Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection may have occurred further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A professional technician can check electrical connections and wiring until they uncover the root 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 make sure it’s not just a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start looking at connectors.
They’ll detach the power and progressively check each wire, seeing to it that they are fully placed into the connector with the proper amount of uncovered copper. Once they find the problem connector, it can be replaced for a new one.
e195 - Critical
This critical error code can surface when the weather outside is especially hot. The HVAC system can shut down and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will subsequently shut down. In the event the breakers are on, you can search a handful of other places before calling a professional technician.
As this error can drain your thermostat’s battery, the first step could be supplying enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and deliver power with a USB cable. Assuming it presents 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 can't detect anything wrong with these components, it will probably be best to call a pro.
e103 - Critical
Another critical error code, e103 indicates an electrical error with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This can stem from the breaker box, an error from the control board or through a bad connection in the thermostat. A technician needs to carefully investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat is convinced there’s an overcurrent problem.
While this error code isn’t critical, it may still stop 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 not having one can block your Nest from obtaining enough 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 resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead be required to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.
e104 - Critical
Just like error code e103, e104 is a critical error stemming from an overcurrent. If excess power is sent through the Nest’s wiring, it may damage internal components and can 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 shut the power off straightaway. You can then get in touch with a professional technician with the necessary experience diagnosing and resolving electrical problems.
e73 - Critical
When your thermostat displays error code e73, it means that the Rc wire is not getting power. This might be as easy as the breaker being shut off, but it may also be something with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually examine the wires to make sure they’re not loose or damaged. If nothing appears to be out of place, it’s a good idea to speak with a local professional.