How to Resolve These Seven Error Codes on Your Nest Thermostat

Operating a Nest thermostat is one of the best ways to improve the daily schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make changes. But as you can expect, it won’t work well or at all if you see an error code show up. The specific error code provides useful information about the underlying problem, something a trained technician can use to provide solutions that much faster.

Listed below are seven of the most likely error codes you could discover on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you might solve it and the projected cost to do so. Keep in mind that while the costs will ultimately hinge on the exact Nest model, you can count on paying around $75-$200 for repairs. This should include things like 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 is displayed when the power is shut off. Because this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on display until the problem is resolved.

Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection could have occurred further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician can inspect electrical connections and wiring until they locate the root of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to ensure 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 gradually inspect each wire, ensuring they are fully inserted into the connector with the correct amount of bare copper. When they locate the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will eventually shut down. In the event the breakers are on, you can search a few other places before contacting a professional technician.

Since this error can consume your thermostat’s battery, the first step may be restoring 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 through a USB cable. Assuming it presents error code 195, you may continue to visually check components including the wiring as well as your air conditioner’s air filter or drainage system. If you can’t find anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 will 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 because of a bad connection in the thermostat. Your technician needs to meticulously examine 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

Even though this error code isn’t critical, it may still stop you from using the Nest thermostat how you prefer 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 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 need a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 be displayed. 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

Like error code e103, e104 is a critical error that’s the result of an overcurrent. If excessive power is transported through the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to shut the power off straightaway. You can then contact a professional technician with the necessary experience diagnosing and fixing electrical problems.

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 something 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 looks to be out of place, it’s a good idea to contact a local professional.