How to Resolve These Seven Error Codes on Your Nest Thermostat

Operating a Nest thermostat is one of the most convenient ways to perfect the day-to-day schedule of your comfort system. This smart thermostat can learn your preferences and automatically make adjustments. But as you may 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 knowledgeable technician can use to present solutions that much sooner.

Let’s consider 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 might solve it and the projected cost to do so. Don’t forget that while the costs will ultimately depend on the exact Nest model, you can expect to pay about $75-$200 for repairs. This should include travel and labor costs as well as any specific hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and appears when the power is disconnected from the system. As this is a critical power error, the thermostat will swap to the backup battery system. The error message will continue to be displayed until the issue is dealt with.

Losing power to your Nest thermostat can be for several reasons. The wiring might have disconnected or become damaged, or a disconnection might have appeared further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician will check electrical connections and wiring until they find the source 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 conduct a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start inspecting connectors.

They’ll detach the power and slowly inspect each wire, making sure they are fully attached into the connector with the correct amount of bare copper. After they pinpoint the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly 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 finally shut down. In the event the breakers are on, you can search a couple of other places before calling a professional technician.

Because this error can consume your thermostat’s battery, the first step might be providing enough power to figure out if this specific error code is what you’re working with. You can separate the thermostat from its base and provide power through a USB cable. If it presents error code 195, you may continue to visually check components such as the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to find anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical issue with your Nest thermostat. More specifically, e103 may 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 bad connection in the thermostat. Your technician can 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.

n260

Although this error code isn’t critical, it may still prevent 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 receiving sufficient power. You can check the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you’ll need a Nest Power Connector.

Due to installation of a Nest Power Connector, you might notice error code E297 appear. This can be remedied 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

Similar to error code e103, e104 is a critical error stemming from an overcurrent. If excessive power is sent through the Nest’s wiring, it may damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to protect from electrical damage, it’s suggested to shut the power off straightaway. You can then get in touch with a professional technician with the appropriate experience identifying and fixing electrical issues.

e73 – Critical

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

This may be as easy as the breaker being turned 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 inspect the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s a good idea to speak with a local professional.