Operating a Nest thermostat is one of the most convenient ways to improve the everyday schedule of your heating and cooling. This smart thermostat can be taught your preferences and automatically make changes. But as you may expect, it won’t work correctly or at all if you see an error code appear. The specific error code offers useful information about the root of the problem, something a knowledgeable technician can use to offer solutions that much sooner.

Here are seven of the most common 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 could solve it and the projected cost to do so. Remember that while the investment will ultimately hinge on the precise Nest model, you can count on paying around $75-$200 for repairs. This should also cover travel and labor costs as well as any specific components required to wrap up repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and shows up when the power is detached from the system. As this is a critical power error, the thermostat will switch to the backup battery system. The error message will continue to be displayed until the problem is dealt with.

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

e294 – Critical

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

They’ll disconnect the power and slowly inspect each wire, ensuring they are fully inserted into the connector with the proper amount of bare copper. When they find the damaged connector, it can be swapped for a new one.

e195 – Critical

This critical error code can surface when the weather outside is severely hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally turn off. Assuming the breakers are on, you can check a handful of other places before contacting a professional technician.

As this error can drain your thermostat’s battery, the first step may be providing enough power to determine 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 displays error code 195, you can continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to find anything wrong with these components, it’s maybe best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is getting 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. The technician should carefully inspect and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it may still stop you from using the Nest thermostat how you want to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining adequate 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 need a Nest Power Connector.

Due to installation of a Nest Power Connector, you will sometimes 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 stemming from an overcurrent. If excessive power is sent through the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to shut the power off as soon as possible. You can then get a hold of a professional technician with the necessary experience identifying and fixing electrical malfunctions.

e73 – Critical

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

This could be as straightforward as the breaker being switched off, but it could also be an issue with the wiring. After turning off the power to your HVAC system and thermostat, you can visually check the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s best to contact a local professional.