Operating a Nest thermostat is one of the best ways to optimize the daily schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make adjustments. But as you can expect, it won’t work correctly or at all if you see an error code show up. The specific error code offers useful information about the root of the problem, something a trained technician can use to offer solutions that much quicker.
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 along with how you could fix it and the projected cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can expect to pay about $75-$200 for repairs. This should include travel and labor costs as well as any specific components needed to complete repairs.
e298 - Critical
This critical error code is limited to newer models of the Nest thermostat and shows up when the power is shut off. Because this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on display until the problem is dealt with.
Losing power to your Nest thermostat can be for several reasons. The wiring may have disconnected or become damaged, or a disconnection could have occurred further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will inspect electrical connections and wiring until they uncover 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 should reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin looking at connectors.
They’ll detach the power and progressively inspect each wire, seeing to it that they are fully inserted into the connector with the proper amount of exposed copper. Once they find the problem connector, it can be replaced for a new one.
e195 - Critical
This critical error code can appear when the weather outside is especially hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will subsequently power down. Assuming the breakers are on, you can search a handful of other places before consulting a professional technician.
Because this error can drain your thermostat’s battery, the first step might be supplying enough power to determine if this specific error code is what you’re facing. You can separate the thermostat from its base and provide power by using a USB cable. In the event it displays error code 195, you can continue to visually examine components like the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it's maybe best to contact a pro.
e103 - Critical
Another critical error code, e103 signifies 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 what is safe and normal. This can stem from the breaker box, an error from the control board or thanks to a bad connection in the thermostat. The technician can cautiously investigate 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.
Although 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 the absence of one can block your Nest from getting enough power. You can examine 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.
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 is already installed, you’ll instead be required 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 excessive power is sent using the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to shut the power off straightaway. You can then get in touch with a professional technician with the necessary experience identifying and fixing electrical issues.
e73 - Critical
When your thermostat displays error code e73, it means that the Rc wire is not receiving power. This will sometimes be as straightforward as the breaker being shut off, but it may also be a problem with the wiring. After switching off the power to your HVAC system and thermostat, you can visually check the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s time to speak with a local professional.