Installing a Nest thermostat is one of the most convenient ways to perfect the day-to-day schedule of your comfort system. 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 exact error code offers useful information about the root of the problem, something a trained technician can use to offer solutions that much faster.

Let’s consider seven of the most frequent error codes you might discover on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you can solve it and the projected cost to do so. Remember that while the price will ultimately depend on the exact Nest model, you can count on paying around $75-$200 for repairs. This should include travel and labor costs as well as any specific hardware necessary to complete repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is shut off. Since this is a critical power error, the thermostat will switch 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 may have disconnected or become damaged, or a disconnection might have appeared further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A trained technician will inspect electrical connections and wiring until they uncover the root of the problem.

e294 – Critical

Critical error code e294 is displayed 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 ensure it’s not simply a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin inspecting connectors.

They’ll shut off the power and slowly look at each wire, making sure they are fully attached into the connector with the correct amount of uncovered copper. After they locate the damaged 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 persists, the backup battery in your thermostat depletes and the thermostat will eventually power down. Assuming the breakers are on, you can examine a handful of other places before consulting a professional technician.

Since 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 dealing with. You can separate the thermostat from its base and supply power with a USB cable. In the event it presents 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 don’t find anything wrong with these components, it will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 may 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 should carefully examine and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it can still keep 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 the absence of one can block your Nest from getting enough power. You can inspect 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.

During 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 is already installed, you’ll instead have 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 originating from an overcurrent. If too much power is being delivered using the Nest’s wiring, it could damage internal components and may 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 suggested to shut the power off as soon as possible. You can then get a hold of a professional technician with the necessary experience detecting and fixing electrical damage.

e73 – Critical

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

This will sometimes be as easy as the breaker being turned 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 inspect the wires to make sure nothing is loose or damaged. If nothing looks to be out of place, it’s a good idea to speak with a local professional.