Installing a Nest thermostat is one of the best ways to improve the everyday schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make changes. But as you can expect, it won’t work properly or at all if you see an error code appear. The exact error code offers useful information about the source of the problem, something a professional technician can use to offer solutions that much sooner.

Let’s consider seven of the most likely error codes you might encounter on your Nest thermostat. We’ll explain the basics of each error code along with how you might address it and the approximate cost to do so. Keep in mind that while the price will ultimately depend on the specific Nest model, you can anticipate paying around $75-$200 for repairs. This should include travel and labor costs as well as any specific components 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. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on the screen until the issue is fixed.

Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection could have appeared further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician can inspect electrical connections and wiring until they locate 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 conduct a factory reset of your thermostat to make sure it’s not just a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin looking at connectors.

They’ll disconnect the power and slowly look at each wire, seeing to it that they are fully inserted into the connector with the proper amount of exposed copper. Once they pinpoint the problem connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can surface when the weather outside is severely hot. The HVAC system can shut down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will finally shut down. In the event the breakers are on, you can search a handful of other places before contacting 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 facing. You can separate the thermostat from its base and provide power with a USB cable. Assuming it reveals error code 195, you can continue to visually examine components such as 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 probably 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 what is safe and normal. This may stem from the breaker box, an error from the control board or through a defective connection in the thermostat. A technician needs to cautiously inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

While this error code isn’t critical, it may still prevent you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from receiving sufficient power. You can check the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you can get a Nest Power Connector.

Due to 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 be required to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Similar to error code e103, e104 is a critical error originating from an overcurrent. If too much power is transported inside the Nest’s wiring, it can damage internal components and may 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 a good idea to turn the power off as soon as you can. You can then get a hold of a professional technician with the appropriate experience detecting and solving electrical problems.

e73 – Critical

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

This could be as simple as the breaker being turned off, but it could also be something with the wiring. After turning off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing appears to be out of place, it’s a good idea to contact a local professional.