How to Resolve These Seven Error Codes on Your Nest Thermostat

Using a Nest thermostat is one of the most convenient ways to optimize the daily schedule of your comfort system. This smart thermostat can learn your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code show up. The exact error code offers useful information about the root of the problem, something a knowledgeable technician can use to offer solutions that much faster.

Let’s consider seven of the most likely error codes you might find on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can address it and the projected cost to do so. Keep in mind that while the price 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 on top of any specific parts necessary to finish 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. Since 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 resolved.

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

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring needs to be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not merely a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start looking at connectors.

They’ll disconnect the power and gradually look at each wire, ensuring they are fully attached into the connector with the proper amount of uncovered copper. When they locate the malfunctioning connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will eventually power down. Presuming the breakers are on, you can check a few other places before calling a professional technician.

Because this error can drain your thermostat’s battery, the first step might be restoring enough power to find out if this specific error code is what you’re working with. You can disconnect the thermostat from its base and supply power by using a USB cable. If 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 get in touch with a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This will sometimes stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. Your technician will meticulously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it could still stop you from using the Nest thermostat like normal. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as missing 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 modify 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 remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 being delivered inside 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 a good idea to shut the power off straightaway. You can then get in touch with a professional technician with the appropriate experience diagnosing and solving electrical issues.

e73 – Critical

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

This will sometimes be as simple as the breaker being switched off, but it can also be an issue with the wiring. After switching off the power to your HVAC system and thermostat, you can visually examine the wires to make sure nothing is loose or damaged. If nothing appears to be out of place, it’s best to get in touch with a local professional.