Installing a Nest thermostat is one of the most convenient ways to optimize the day-to-day schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make adjustments. But as you might expect, it won’t work well or at all if you see an error code on the display. The exact error code supplies useful information about the source of the problem, something a knowledgeable technician can use to provide solutions that much sooner.

Let’s consider seven of the most frequent error codes you could find on your Nest thermostat. We’ll review the basics of each error code as well as how you can address it and the approximate cost to do so. Keep in mind that while the costs will ultimately be dependent on the specific Nest model, you can anticipate paying about $75-$200 for repairs. This should also cover travel and labor costs along with any specific components necessary to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears when the power is disconnected from the system. 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 problem is dealt with.

Losing power to your Nest thermostat can be for several reasons. The wiring might have disconnected or become damaged, or a disconnection could have appeared further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A knowledgeable technician should check electrical connections and wiring until they find 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, 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 problem. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start looking at connectors.

They’ll shut off the power and slowly look at each wire, seeing to it that they are fully inserted into the connector with the proper amount of exposed copper. After they pinpoint the malfunctioning 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 sending power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will finally shut down. Presuming the breakers are on, you can check a couple of other places before consulting a professional technician.

Because this error can drain your thermostat’s battery, the first step may be supplying enough power to figure out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and supply power by using a USB cable. Assuming it displays error code 195, you can 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 call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical issue with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This may stem from the breaker box, an error from the control board or through a defective connection in the thermostat. Your technician needs to meticulously investigate and test the Nest’s electrical system to determine where the power is surging or why the thermostat is convinced there’s an overcurrent problem.

n260

While this error code isn’t critical, it might still stop you from using the Nest thermostat like normal. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting 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 can get a Nest Power Connector.

Due to installation of a Nest Power Connector, you might notice error code E297 be displayed. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already 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 excess power is transported inside the Nest’s wiring, it can 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 recommended to shut the power off straightaway. You can then get in touch with a professional technician with the appropriate experience identifying and fixing electrical problems.

e73 – Critical

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

This will sometimes be as simple as the breaker being switched off, but it may also be something with the wiring. After switching 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 speak with a local professional.