Using a Nest thermostat is one of the most convenient ways to optimize 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 appear. The specific 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 common error codes you might encounter on your Nest thermostat. We’ll review 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 price will ultimately be dependent on the specific Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs as well as any specific parts required to complete repairs.
e298 - Critical
This critical error code is limited to new models of the Nest thermostat and appears when the power is shut off. As this is a critical power error, the thermostat will swap 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 numerous reasons. The wiring could have disconnected or become damaged, or a disconnection could have occurred further along in your home's electrical system. This could be the circuit breaker, fuse box or system switch. A trained technician can inspect 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 conduct a factory reset of your thermostat to ensure it’s not merely a software error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin checking connectors.
They’ll shut off the power and gradually inspect each wire, ensuring they are fully placed into the connector with the proper amount of bare copper. After they find the problem connector, it can be exchanged for a new one.
e195 - Critical
This critical error code can surface when the weather outside is particularly hot. The HVAC system can fail and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will eventually shut down. Assuming the breakers are on, you can check a handful of other places before consulting a professional technician.
As this error can deplete your thermostat’s battery, the first step might be supplying enough power to determine if this specific error code is what you’re dealing with. You can disconnect the thermostat from its base and provide power through a USB cable. In the event it presents error code 195, you can continue to visually check components like 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's maybe best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 suggests an electrical issue with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This will sometimes stem from the breaker box, an error from the control board or through a defective connection in the thermostat. The technician can meticulously examine and test the Nest’s electrical system to understand 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 prevent you from using the Nest thermostat how you prefer to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from receiving 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’ll need a Nest Power Connector.
With installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been installed, you’ll instead need 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 stemming from an overcurrent. If too much power is transported through the Nest’s wiring, it can damage internal components and could even be a fire hazard. If you see this error code show up on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off straightaway. You can then get in touch with a professional technician with the proper experience detecting and resolving electrical damage.
e73 - Critical
When your thermostat displays error code e73, it indicates that the Rc wire is not receiving power. This will sometimes be as simple as the breaker being turned 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 they’re not loose or damaged. If nothing looks to be out of place, it’s a good idea to speak with a local professional.