How to Resolve These Seven Error Codes on Your Nest Thermostat

Installing a Nest thermostat is one of the best ways to perfect the everyday schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make changes. But as you might expect, it won’t work properly or at all if you see an error code on the display. The exact error code provides useful information about the underlying problem, something a knowledgeable technician can use to present solutions that much quicker.

Listed below are seven of the most common error codes you could discover on your Nest thermostat. We’ll review the basics of each error code along with how you might fix it and the projected cost to do so. Keep in mind that while the investment will ultimately depend on the exact Nest model, you can anticipate paying around $75-$200 for repairs. This should include things like travel and labor costs along with any specific hardware required to wrap up repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed when the power is shut off. As this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on the screen until the issue is resolved.

Losing power to your Nest thermostat can be for a number of reasons. The wiring might have disconnected or become damaged, or a disconnection may have appeared further along in the electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician should check electrical connections and wiring until they find the source of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring has to 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 just a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin checking connectors.

They’ll disconnect the power and gradually check each wire, making sure they are fully inserted into the connector with the correct amount of exposed copper. When they locate the malfunctioning connector, it can be replaced 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 sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will subsequently power down. Presuming the breakers are on, you can search a handful of other places before calling a professional technician.

Because this error can drain your thermostat’s battery, the first step might be providing enough power to find out if this specific error code is what you’re working with. You can detach the thermostat from its base and provide power through a USB cable. Assuming it reveals error code 195, you should continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t uncover anything wrong with these components, it will probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical malfunction with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing 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 should cautiously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it could still stop you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining enough power. You can check the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you’ll need a Nest Power Connector.

Due to 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 has already been 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 originating from an overcurrent. If excessive power is transported inside the Nest’s wiring, it could damage internal components and could 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 a good idea to turn the power off as soon as possible. You can then get a hold of a professional technician with the proper experience identifying and solving electrical malfunctions.

e73 – Critical

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

This will sometimes be as simple as the breaker being turned off, but it may also be an issue with the wiring. After shutting 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 seems to be out of place, it’s time to get in touch with a local professional.