How to Resolve These Seven Error Codes on Your Nest Thermostat

August 15, 2022

Installing a Nest thermostat is one of the easiest ways to perfect the day-to-day schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make improvements. But as you can expect, it won’t work correctly or at all if you see an error code appear. The precise error code supplies useful information about the root of the problem, something a knowledgeable technician can use to provide solutions that much sooner.

Let's consider seven of the most frequent error codes you might find on your Nest thermostat. We’ll explain the basics of each error code as well as how you can address it and the projected cost to do so. Keep in mind that while the costs will ultimately be dependent on the exact Nest model, you can anticipate paying about $75-$200 for repairs. This should include travel and labor costs on top of any specific hardware needed to wrap up repairs.

e298 - Critical

This critical error code is limited to new models of the Nest thermostat and is displayed 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 dealt with.

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

They’ll shut off the power and progressively inspect each wire, seeing to it that they are fully attached into the connector with the correct amount of bare copper. When they locate the malfunctioning connector, it can be swapped for a new one.

e195 - Critical

This critical error code can appear when the weather outside is especially hot. The HVAC system can shut 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 turn off. Assuming the breakers are on, you can inspect a couple of other places before consulting a professional technician.

Since 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 facing. You can separate the thermostat from its base and deliver power through a USB cable. If it presents error code 195, you may continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to detect anything wrong with these components, it will probably be best to call a pro.

e103 - Critical

Another critical error code, e103 suggests an electrical malfunction with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This may stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. The technician can meticulously investigate and test the Nest’s electrical system to determine 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 not having one can block your Nest from obtaining enough 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’ll need a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 appear. This can be dealt with 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 that's the result of an overcurrent. If excessive power is transported inside the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you notice this error code show up on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to turn the power off as soon as possible. You can then contact a professional technician with the necessary experience identifying and solving electrical issues.

e73 - Critical

When your thermostat displays error code e73, it means that the Rc wire is not getting power. This might be as simple as the breaker being shut off, but it may also be a problem 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 best to get in touch with a local professional.