Using a Nest thermostat is one of the best ways to optimize the everyday schedule of your HVAC system. This smart thermostat can recognize your preferences and automatically make changes. But as you might expect, it won’t work well or at all if you see an error code show up. The specific error code offers useful information about the root of the problem, something a knowledgeable technician can use to provide solutions that much sooner.
Let's consider seven of the most frequent error codes you could find on your Nest thermostat. We’ll walk you through the basics of each error code as well as how you might address it and the estimated cost to do so. Remember that while the costs will ultimately hinge on the precise Nest model, you can anticipate paying around $75-$200 for repairs. This should include things like travel and labor costs as well as 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 disconnected from the system. Since this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on the screen until the issue is fixed.
Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection might have appeared further along in your electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician should 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 needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first conduct 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 looking at connectors.
They’ll disconnect the power and gradually check each wire, making sure they are fully placed into the connector with the proper amount of uncovered copper. Once they find the malfunctioning connector, it can be swapped for a new one.
e195 - Critical
This critical error code can surface when the weather outside is severely hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will subsequently power down. Presuming the breakers are on, you can check a few 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 figure out if this specific error code is what you’re facing. You can disconnect the thermostat from its base and supply power with a USB cable. If it displays error code 195, you can continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you don’t detect anything wrong with these components, it will probably be best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 signifies an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than what is safe and normal. This will sometimes stem from the breaker box, an error from the control board or thanks to a defective connection in the thermostat. Your technician should cautiously examine and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.
Although this error code isn’t critical, it could still stop you from using the Nest thermostat how you prefer to. Error code n260 pertains to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from receiving sufficient power. You can inspect 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.
With installation of a Nest Power Connector, you will sometimes notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector was 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 that's the result of an overcurrent. If too much power is transported using the Nest’s wiring, it could damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to turn the power off straightaway. You can then get a hold of a professional technician with the proper experience detecting and solving electrical damage.
e73 - Critical
When your thermostat displays error code e73, it means that the Rc wire is not getting power. This will sometimes be as easy as the breaker being switched off, but it can also be something with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually check the wires to make sure they’re not loose or damaged. If nothing looks to be out of place, it’s time to speak with a local professional.