Operating a Nest thermostat is one of the most convenient ways to perfect the day-to-day schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make changes. But as you can expect, it won’t work correctly or at all if you see an error code on the display. The precise error code provides useful information about the root of the problem, something a professional technician can use to offer solutions that much sooner.
Here are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you can solve it and the approximate cost to do so. Keep in mind that while the costs will ultimately depend on the specific Nest model, you can anticipate paying around $75-$200 for repairs. This should include things like travel and labor costs on top of any specific hardware necessary to finish repairs.
e298 - Critical
This critical error code is limited to new models of the Nest thermostat and shows up when the power is disconnected from the system. Because this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on display until the problem is fixed.
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 home's electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician will check electrical connections and wiring until they find the source of the problem.
e294 - Critical
Critical error code e294 shows up when your Nest thermostat’s wiring should be reconfigured. More specifically, you’ll need the technician 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 detach the power and slowly look at each wire, seeing to it that they are fully placed into the connector with the correct amount of uncovered copper. When they locate the problem connector, it can be exchanged for a new one.
e195 - Critical
This critical error code can surface when the weather outside is especially hot. The HVAC system can break down and stop delivering power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will subsequently turn off. In the event the breakers are on, you can search a handful of other places before calling a professional technician.
As this error can deplete your thermostat’s battery, the first step might be supplying enough power to find out if this specific error code is what you’re facing. You can separate the thermostat from its base and deliver power by using a USB cable. In the event 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 find anything wrong with these components, it's maybe best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 suggests 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 needed. This can stem from the breaker box, an error from the control board or through a defective connection in the thermostat. A technician can carefully 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.
Although this error code isn’t critical, it may still stop you from using the Nest thermostat how you prefer to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from getting adequate power. You can check the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you need 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 sent through the Nest’s wiring, it can damage internal components and may 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 resolving electrical damage.
e73 - Critical
When your thermostat displays error code e73, it indicates that the Rc wire is not receiving power. This might be as straightforward as the breaker being switched off, but it could also be a problem with the wiring. After turning 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 contact a local professional.