Using a Nest thermostat is one of the most convenient ways to improve the everyday schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make adjustments. But as you can expect, it won’t work well or at all if you see an error code show up. The exact error code offers useful information about the root of the problem, something a knowledgeable technician can use to offer solutions that much quicker.

Listed below are seven of the most common error codes you could find on your Nest thermostat. We’ll walk you through the basics of each error code along with how you might fix it and the projected cost to do so. Keep in mind that while the costs will ultimately hinge on the precise Nest model, you can expect to pay about $75-$200 for repairs. This should include travel and labor costs along with any specific hardware needed to wrap up repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and appears when the power is detached from the system. As this is a critical power error, the thermostat will change to the backup battery system. The error message will continue to be displayed until the issue is fixed.

Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection might have occurred further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A certified 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 has to 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 simply a software problem. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start inspecting 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 correct amount of bare copper. When they locate the damaged 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 fail and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will finally power down. Presuming the breakers are on, you can inspect a couple of other places before contacting a professional technician.

Since this error can consume your thermostat’s battery, the first step might be supplying enough power to figure out if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and deliver power through a USB cable. Assuming it reveals error code 195, you may continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical issue with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than what is safe and normal. This can stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. Your technician needs to cautiously examine and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it may still prevent you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from receiving adequate power. You can inspect the Nest’s C connector for the presence of a C wire and modify 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 has already been installed, you’ll instead be required 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 stemming from an overcurrent. If too much power is transported inside the Nest’s wiring, it can 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 take steps to prevent electrical damage, it’s suggested to switch the power off as soon as possible. You can then contact 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 getting power.

This will sometimes be as easy as the breaker being shut off, but it may also be an issue with the wiring. After shutting 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 best to contact a local professional.