Operating a Nest thermostat is one of the best ways to improve the daily schedule of your heating and cooling. This smart thermostat can recognize 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 precise error code offers useful information about the underlying problem, something a professional technician can use to provide solutions that much quicker.
Here are seven of the most frequent error codes you could encounter on your Nest thermostat. We’ll explain the basics of each error code along with how you could solve it and the approximate cost to do so. Don't forget that while the price will ultimately hinge on the specific Nest model, you can anticipate paying around $75-$200 for repairs. This should include travel and labor costs along with any specific components necessary to finish repairs.
e298 - Critical
This critical error code is limited to the latest models of the Nest thermostat and shows up when the power is shut off. Because 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 problem is resolved.
Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection might have occurred further along in the electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician should check electrical connections and wiring until they find the root of the problem.
e294 - Critical
Critical error code e294 is displayed when your Nest thermostat’s wiring has to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to ensure it’s not simply a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.
They’ll detach the power and progressively inspect each wire, seeing to it that they are fully attached into the connector with the correct amount of exposed copper. After they find the problem connector, it can be exchanged 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 lingers, the backup battery in your thermostat drains and the thermostat will finally turn off. Assuming the breakers are on, you can check a few other places before consulting a professional technician.
As this error can consume your thermostat’s battery, the first step might be supplying enough power to figure out 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. If it reveals error code 195, you may 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 detect anything wrong with these components, it will likely be best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 suggests an electrical malfunction with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is getting more power than necessary. This may stem from the breaker box, an error from the control board or thanks to a bad connection in the thermostat. Your technician should cautiously examine and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.
Even though this error code isn’t critical, it could still stop you from using the Nest thermostat how you prefer 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 inspect the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you need a Nest Power Connector.
During installation of a Nest Power Connector, you might notice error code E297 appear. This can be dealt with 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
Like error code e103, e104 is a critical error stemming from an overcurrent. If too much power is sent inside 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 take steps to prevent electrical damage, it’s suggested to shut the power off straightaway. You can then get a hold of a professional technician with the necessary experience identifying and solving electrical malfunctions.
e73 - Critical
When your thermostat displays error code e73, it means that the Rc wire is not getting power. This will sometimes be as easy as the breaker being shut off, but it may also be an issue with the wiring. After switching off the power to your HVAC system and thermostat, you can visually examine the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s best to contact a local professional.