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 properly or at all if you see an error code show up. The specific error code offers useful information about the source of the problem, something a knowledgeable technician can use to present solutions that much quicker.

Listed below are seven of the most likely error codes you could discover on your Nest thermostat. We’ll review the basics of each error code on top of how you could fix it and the projected cost to do so. Don’t forget that while the investment will ultimately be dependent on the precise Nest model, you can expect to pay about $75-$200 for repairs. This should include things like travel and labor costs along with any specific parts necessary to complete repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and shows up when the power is detached from the system. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on display until the issue is resolved.

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

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin inspecting 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 uncovered copper. Once they find the malfunctioning connector, it can be replaced for a new one.

e195 – Critical

This critical error code can show up when the weather outside is especially hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will subsequently power down. Presuming the breakers are on, you can inspect a handful of other places before calling a professional technician.

Since this error can deplete 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 separate the thermostat from its base and supply power through a USB cable. Assuming it presents error code 195, you may continue to visually inspect components like 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 likely be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical problem with your Nest thermostat. More specifically, e103 can 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 through a defective connection in the thermostat. A technician can cautiously 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

Although this error code isn’t critical, it might 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 the absence of one can block your Nest from obtaining sufficient 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 might notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead be required 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 excessive power is sent using the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you notice this error code show up on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off straightaway. You can then get in touch with a professional technician with the appropriate experience identifying and fixing electrical malfunctions.

e73 – Critical

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

This may be as simple as the breaker being turned off, but it may also be an issue with the wiring. After turning off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure nothing is loose or damaged. If nothing looks to be out of place, it’s best to get in touch with a local professional.