Installing a Nest thermostat is one of the easiest ways to optimize the everyday schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make changes. But as you might expect, it won’t work well or at all if you see an error code appear. The precise error code supplies useful information about the underlying problem, something a professional technician can use to provide solutions that much sooner.
Here are seven of the most common error codes you could encounter on your Nest thermostat. We’ll explain the basics of each error code on top of how you might solve it and the approximate cost to do so. Keep in mind that while the price will ultimately be dependent on the exact Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs as well as any specific components needed to complete repairs.
e298 - Critical
This critical error code is limited to the latest models of the Nest thermostat and appears when the power is disconnected from the system. 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 dealt with.
Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection might have appeared further along in the electrical system. This may be the circuit breaker, fuse box or system switch. A knowledgeable technician can examine electrical connections and wiring until they find the source of the problem.
e294 - Critical
Critical error code e294 shows up when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure 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 detach the power and progressively check each wire, ensuring they are fully attached into the connector with the correct amount of bare copper. Once they pinpoint 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 break down and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally shut down. Assuming the breakers are on, you can check a couple of other places before consulting a professional technician.
Since this error can consume your thermostat’s battery, the first step might be restoring enough power to find out if this specific error code is what you’re facing. You can detach the thermostat from its base and provide power with a USB cable. If it presents error code 195, you should continue to visually examine components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can't uncover anything wrong with these components, it will likely be best to contact a pro.
e103 - Critical
Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is getting more power than what is safe and normal. This will sometimes stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. Your technician should cautiously inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks there’s an overcurrent problem.
Although this error code isn’t critical, it can 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 missing one can block your Nest from obtaining enough 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 may notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead have 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 originating from an overcurrent. If excessive power is sent using the Nest’s wiring, it may damage internal components and may even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s a good idea to shut the power off as soon as possible. You can then get in touch with a professional technician with the proper experience identifying and solving electrical issues.
e73 - Critical
When your thermostat displays error code e73, it signifies that the Rc wire is not receiving power. This may be as straightforward as the breaker being switched off, but it can also be an issue with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s time to contact a local professional.