Operating a Nest thermostat is one of the best ways to perfect the daily schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make improvements. But as you can expect, it won’t work well or at all if you see an error code show up. The exact error code provides useful information about the root of the problem, something a professional technician can use to provide solutions that much sooner.

Here are seven of the most likely error codes you might discover on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you can address it and the estimated cost to do so. Don’t forget that while the investment will ultimately be dependent on the exact Nest model, you can expect to pay about $75-$200 for repairs. This should also cover travel and labor costs along with any specific hardware needed 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 shut off. Since 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 problem is fixed.

Losing power to your Nest thermostat can be for a number of reasons. The wiring may have disconnected or become damaged, or a disconnection might have happened further along in your home’s electrical system. This may be the circuit breaker, fuse box or system switch. A knowledgeable technician should check 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 needs to be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first perform a factory reset of your thermostat to ensure it’s not simply a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin inspecting connectors.

They’ll detach the power and gradually inspect each wire, seeing to it that they are fully inserted into the connector with the proper amount of bare copper. After they locate the problem 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 shut down and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will eventually shut down. Assuming the breakers are on, you can check a handful of other places before calling a professional technician.

Since this error can deplete your thermostat’s battery, the first step might be restoring enough power to find out if this specific error code is what you’re facing. You can detach the thermostat from its base and supply power with a USB cable. If it reveals error code 195, you should continue to visually check components including the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to uncover anything wrong with these components, it will likely be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical issue with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than needed. This may stem from the breaker box, an error from the control board or because of a defective connection in the thermostat. Your technician should cautiously examine 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

Although this error code isn’t critical, it can still keep you from using the Nest thermostat how you want to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining enough power. You can check the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you’ll need a Nest Power Connector.

Due to installation of a Nest Power Connector, you will sometimes notice error code E297 be displayed. 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

Similar to error code e103, e104 is a critical error stemming from an overcurrent. If excessive power is being delivered using the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to take steps to prevent electrical damage, it’s suggested to turn the power off as soon as you can. You can then get a hold of 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 could be as easy as the breaker being turned 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 none of them are loose or damaged. If nothing seems to be out of place, it’s best to speak with a local professional.