Installing a Nest thermostat is one of the best ways to improve the everyday schedule of your comfort system. This smart thermostat can learn your preferences and automatically make improvements. But as you might expect, it won’t work properly or at all if you see an error code appear. The exact error code supplies useful information about the root of the problem, something a trained technician can use to provide solutions that much faster.
Here are seven of the most frequent error codes you might find on your Nest thermostat. We’ll review the basics of each error code along with how you can address it and the approximate cost to do so. Keep in mind that while the costs will ultimately hinge on the exact Nest model, you can expect to pay around $75-$200 for repairs. This should also cover travel and labor costs along with any specific hardware necessary to complete repairs.
e298 - Critical
This critical error code is limited to new models of the Nest thermostat and appears when the power is detached from the system. As 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 dealt with.
Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection could have appeared further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician can check electrical connections and wiring until they locate the source of the problem.
e294 - Critical
Critical error code e294 appears when your Nest thermostat’s wiring should 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 make sure it’s not simply a software error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.
They’ll detach the power and progressively inspect each wire, making sure they are fully attached into the connector with the correct amount of exposed copper. Once they locate the malfunctioning connector, it can be exchanged for a new one.
e195 - Critical
This critical error code can appear when the weather outside is severely 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 depletes and the thermostat will subsequently power down. Presuming the breakers are on, you can examine a couple of other places before consulting a professional technician.
Because this error can drain your thermostat’s battery, the first step could be providing 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 deliver power through a USB cable. Assuming it presents error code 195, you should continue to visually inspect components including 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's maybe best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 indicates an electrical error with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This can stem from the breaker box, an error from the control board or through a faulty connection in the thermostat. A technician should meticulously investigate and test the Nest’s electrical system to figure out where the power is surging or why the thermostat is convinced there’s an overcurrent problem.
Even though this error code isn’t critical, it could still stop 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 not having one can block your Nest from obtaining adequate power. You can examine the Nest’s C connector for the presence of a C wire and adapt the wiring itself if there is. If not, you can get a Nest Power Connector.
With installation of a Nest Power Connector, you might notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was already installed, you’ll instead be required to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.
e104 - Critical
Like error code e103, e104 is a critical error that's the result of an overcurrent. If excess power is transported through the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you see this error code appear on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off straightaway. You can then contact a professional technician with the proper experience detecting and resolving electrical damage.
e73 - Critical
When your thermostat displays error code e73, it means that the Rc wire is not receiving power. This may be as simple as the breaker being switched off, but it may 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 nothing is loose or damaged. If nothing looks to be out of place, it’s a good idea to get in touch with a local professional.