How to Resolve These Seven Error Codes on Your Nest Thermostat

August 15, 2022

Operating a Nest thermostat is one of the best ways to improve the everyday schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make improvements. But as you can expect, it won’t work properly or at all if you see an error code show up. The precise error code supplies useful information about the underlying problem, something a professional technician can use to provide solutions that much quicker.

Listed below are seven of the most likely error codes you may find on your Nest thermostat. We’ll explain the basics of each error code as well as how you might fix it and the projected cost to do so. Keep in mind that while the price will ultimately hinge on the specific Nest model, you can count on paying about $75-$200 for repairs. This should include travel and labor costs along with any specific parts necessary to finish repairs.

e298 - Critical

This critical error code is limited to newer models of the Nest thermostat and shows up when the power is detached 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 display until the issue is resolved.

Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection could have appeared further along in your home's electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician can examine electrical connections and wiring until they locate 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, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not merely a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin inspecting connectors.

They’ll disconnect the power and gradually check each wire, seeing to it that they are fully attached into the connector with the correct amount of uncovered copper. When they locate the malfunctioning 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 break down and stop delivering power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will finally power down. Presuming the breakers are on, you can search a handful of other places before calling a professional technician.

Since this error can deplete your thermostat’s battery, the first step may be restoring enough power to find out if this specific error code is what you’re facing. You can disconnect the thermostat from its base and provide power by using a USB cable. If it reveals error code 195, you may continue to visually examine components such as 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 will probably be best to get in touch with a pro.

e103 - Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than needed. This can stem from the breaker box, an error from the control board or through a bad connection in the thermostat. The technician needs to cautiously 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

Although this error code isn’t critical, it might still stop you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from receiving adequate 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.

Due to installation of a Nest Power Connector, you might notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead need to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 - Critical

Just like error code e103, e104 is a critical error originating from an overcurrent. If excessive power is sent using the Nest’s wiring, it can damage internal components and can even be a fire hazard. If you see this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s suggested to shut the power off as soon as possible. You can then get a hold of a professional technician with the necessary experience identifying and solving electrical damage.

e73 - Critical

When your thermostat displays error code e73, it means that the Rc wire is not receiving power. This might be as easy as the breaker being shut off, but it may also be something with the wiring. After turning 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 time to get in touch with a local professional.