Using a Nest thermostat is one of the best ways to perfect the daily schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code on the display. The precise error code offers useful information about the source of the problem, something a trained technician can use to present solutions that much quicker.

Listed below are seven of the most likely error codes you could find on your Nest thermostat. We’ll explain the basics of each error code as well as how you might fix it and the projected cost to do so. Keep in mind that while the costs will ultimately be dependent on the exact Nest model, you can anticipate paying about $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts 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. As this is a critical power error, the thermostat will swap 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 could have disconnected or become damaged, or a disconnection might have occurred further along in your home’s electrical system. This may be the circuit breaker, fuse box or system switch. A knowledgeable technician can inspect electrical connections and wiring until they locate the root of the problem.

e294 – Critical

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

They’ll disconnect the power and gradually look at each wire, ensuring they are fully inserted into the connector with the proper amount of bare copper. After they pinpoint 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 break down and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will eventually shut down. In the event the breakers are on, you can examine a few other places before calling a professional technician.

As this error can drain your thermostat’s battery, the first step may be restoring enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and provide power with a USB cable. Assuming it reveals error code 195, you should continue to visually check components like the wiring as well as your air conditioner’s air filter or drainage system. If you can’t detect anything wrong with these components, it will probably be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical error 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 because of a defective connection in the thermostat. A technician can cautiously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it might still keep you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from receiving adequate 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.

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 has already been installed, you’ll instead need to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Similar to error code e103, e104 is a critical error stemming from an overcurrent. If excess power is sent inside the Nest’s wiring, it could damage internal components and can 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 a good idea to switch the power off as soon as possible. You can then get a hold of a professional technician with the proper experience diagnosing and fixing electrical malfunctions.

e73 – Critical

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

This could be as simple as the breaker being turned off, but it can also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s best to get in touch with a local professional.