Here's What These 7 Nest Thermostat Error Codes Mean

Installing a Nest thermostat is one of the most convenient ways to improve the everyday 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 correctly or at all if you see an error code show up. The exact error code supplies useful information about the source of the problem, something a knowledgeable technician can use to offer solutions that much sooner.

Here are seven of the most likely error codes you might encounter on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you can fix it and the projected cost to do so. Don’t forget that while the investment will ultimately be dependent on the exact Nest model, you can expect to pay between $75-$200 for repairs. This should include travel and labor costs along with any specific components needed 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 disconnected from the system. Since this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on display until the issue is fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring may have disconnected or become damaged, or a disconnection might have occurred further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A professional technician will 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 needs to be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to ensure it’s not simply a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin checking connectors.

They’ll disconnect the power and progressively check each wire, seeing to it that they are fully placed into the connector with the correct amount of bare copper. When they pinpoint the problem 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 sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will subsequently power down. Assuming the breakers are on, you can examine a handful of other places before calling a professional technician.

As this error can consume your thermostat’s battery, the first step might be providing enough power to figure out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and supply power through a USB cable. In the event 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 find anything wrong with these components, it will likely be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is experiencing more power than what is safe and normal. This can stem from the breaker box, an error from the control board or through a bad connection in the thermostat. The technician can meticulously investigate and test the Nest’s electrical system to figure out 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 keep you from using the Nest thermostat like normal. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining adequate power. You can inspect the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you can get a Nest Power Connector.

Due to installation of a Nest Power Connector, you might notice error code E297 show up. This can be dealt with by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead have 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 being delivered inside the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s suggested to switch the power off as soon as you can. You can then get a hold of a professional technician with the proper experience diagnosing and resolving electrical damage.

e73 – Critical

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

This will sometimes be as straightforward as the breaker being turned off, but it may also be an issue with the wiring. After switching 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 seems to be out of place, it’s a good idea to contact a local professional.