Operating a Nest thermostat is one of the easiest ways to improve the everyday schedule of your comfort system. This smart thermostat can learn your preferences and automatically make improvements. But as you might expect, it won’t work well or at all if you see an error code on the display. The specific error code provides useful information about the root of the problem, something a knowledgeable technician can use to present solutions that much quicker.

Listed below are seven of the most frequent error codes you could encounter on your Nest thermostat. We’ll review the basics of each error code on top of how you might fix it and the estimated cost to do so. Remember that while the costs will ultimately be dependent on the precise Nest model, you can anticipate paying between $75-$200 for repairs. This should include travel and labor costs along with any specific hardware needed 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. Because 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 a number of reasons. The wiring may have disconnected or become damaged, or a disconnection might have appeared further along in the electrical system. This might be the circuit breaker, fuse box or system switch. A professional technician should check electrical connections and wiring until they find the source of the problem.

e294 – Critical

Critical error code e294 shows up 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 complete a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin looking at connectors.

They’ll disconnect the power and gradually inspect each wire, making sure they are fully placed into the connector with the proper amount of exposed copper. After they find the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can surface when the weather outside is severely hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will eventually power down. Assuming the breakers are on, you can check a couple of other places before consulting a professional technician.

As this error can deplete 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 separate the thermostat from its base and supply power through a USB cable. Assuming it presents error code 195, you can continue to visually check 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 will probably be best to call 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 can stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. The technician needs to carefully 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

Although this error code isn’t critical, it may still stop you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting enough power. You can examine the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you’ll need a Nest Power Connector.

Due to installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 excessive power is sent using the Nest’s wiring, it may damage internal components and may 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 recommended to turn the power off as soon as you can. You can then get a hold of a professional technician with the necessary experience detecting and solving electrical issues.

e73 – Critical

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

This might be as easy as the breaker being switched off, but it could also be an issue with the wiring. After switching 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 looks to be out of place, it’s a good idea to contact a local professional.