Using a Nest thermostat is one of the easiest ways to optimize the everyday schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make adjustments. But as you can expect, it won’t work correctly or at all if you see an error code on the display. The precise error code provides useful information about the root of the problem, something a professional technician can use to provide solutions that much faster.

Listed below are seven of the most likely error codes you could encounter on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can fix it and the estimated cost to do so. Remember that while the investment will ultimately hinge on the specific Nest model, you can count on paying about $75-$200 for repairs. This should include travel and labor costs as well as any specific components required to complete repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears 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 continue to be displayed until the issue is dealt with.

Losing power to your Nest thermostat can be for numerous reasons. The wiring could have disconnected or become damaged, or a disconnection might have happened further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician should inspect electrical connections and wiring until they locate the source of the problem.

e294 – Critical

Critical error code e294 shows up 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 conduct a factory reset of your thermostat to make sure it’s not simply a software problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and begin checking connectors.

They’ll shut off the power and slowly inspect each wire, seeing to it that they are fully attached into the connector with the correct amount of uncovered copper. When they locate 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 shut down and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will eventually power down. Assuming the breakers are on, you can inspect a couple of other places before contacting a professional technician.

Because this error can consume your thermostat’s battery, the first step could be providing enough power to figure out if this specific error code is what you’re facing. You can disconnect the thermostat from its base and deliver power by using a USB cable. In the event it reveals error code 195, you should continue to visually check 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 call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is getting more power than necessary. This may stem from the breaker box, an error from the control board or because of a faulty connection in the thermostat. A technician needs to meticulously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it may still keep you from using the Nest thermostat how you want to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from receiving enough power. You can examine 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.

During installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead have to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Just 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 may damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to guard against electrical damage, it’s recommended to shut the power off as soon as possible. You can then get a hold of a professional technician with the appropriate experience detecting and fixing electrical malfunctions.

e73 – Critical

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

This may be as easy as the breaker being shut off, but it can also be something with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually examine the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s a good idea to contact a local professional.