Operating a Nest thermostat is one of the best ways to perfect the daily schedule of your HVAC system. This smart thermostat can be taught your preferences and automatically make changes. But as you can expect, it won’t work properly or at all if you see an error code appear. The specific error code provides useful information about the underlying problem, something a professional technician can use to offer solutions that much quicker.

Here are seven of the most frequent error codes you might encounter on your Nest thermostat. We’ll explain the basics of each error code on top of how you could solve it and the projected cost to do so. Remember 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 components necessary to finish repairs.

e298 – Critical

This critical error code is limited to newer models of the Nest thermostat and is displayed 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 continue to be displayed until the issue is resolved.

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 home’s electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician will examine electrical connections and wiring until they find the source of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not merely a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start inspecting connectors.

They’ll shut off the power and progressively look at each wire, making sure they are fully inserted into the connector with the correct amount of bare copper. When they locate the problem connector, it can be replaced for a new one.

e195 – Critical

This critical error code can surface when the weather outside is especially hot. The HVAC system can shut down and stop delivering power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will finally turn off. In the event the breakers are on, you can inspect a couple of other places before consulting a professional technician.

Because this error can deplete your thermostat’s battery, the first step may be providing 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 through a USB cable. If it reveals error code 195, you can continue to visually check components such as the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to detect anything wrong with these components, it will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This can stem from the breaker box, an error from the control board or thanks to a faulty connection in the thermostat. Your technician should carefully inspect 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 prevent you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing 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 can get a Nest Power Connector.

During installation of a Nest Power Connector, you might notice error code E297 show up. This can be dealt with 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

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 may damage internal components and could even be a fire hazard. If you see this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to shut the power off as soon as you can. You can then contact a professional technician with the appropriate experience detecting and solving electrical damage.

e73 – Critical

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

This might be as simple as the breaker being switched off, but it can also be a problem with the wiring. After turning off the power to your HVAC system and thermostat, you can visually examine the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s time to speak with a local professional.