Installing a Nest thermostat is one of the best ways to improve the daily 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 well or at all if you see an error code on the display. The exact error code offers useful information about the root of the problem, something a professional technician can use to offer solutions that much quicker.

Listed below are seven of the most likely error codes you might encounter on your Nest thermostat. We’ll review the basics of each error code along with how you can fix it and the projected cost to do so. Keep in mind that while the costs will ultimately depend on the precise Nest model, you can anticipate paying about $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts required 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. 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 problem is dealt with.

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

e294 – Critical

Critical error code e294 shows up when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first perform a factory reset of your thermostat to ensure it’s not simply a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and start looking at connectors.

They’ll shut off the power and gradually look at each wire, making sure they are fully placed into the connector with the proper amount of bare 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 delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally power down. In the event the breakers are on, you can inspect a handful of other places before contacting a professional technician.

Since this error can consume your thermostat’s battery, the first step might be restoring enough power to determine if this specific error code is what you’re working with. You can detach the thermostat from its base and supply power through a USB cable. In the event 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 probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 suggests 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 may stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. A technician will carefully inspect 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 might still prevent you from using the Nest thermostat how you prefer to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining adequate power. You can inspect 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 might notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already 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 that’s the result of an overcurrent. If too much power is being delivered through the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you see this error code show up on your Nest thermostat and want to guard against electrical damage, it’s a good idea to shut the power off straightaway. You can then get a hold of a professional technician with the appropriate experience diagnosing and solving electrical problems.

e73 – Critical

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

This may be as easy as the breaker being turned off, but it may also be something with the wiring. After turning 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 get in touch with a local professional.