Using a Nest thermostat is one of the easiest ways to perfect the daily schedule of your comfort system. This smart thermostat can recognize your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code on the display. The specific error code provides useful information about the source of the problem, something a trained technician can use to present solutions that much quicker.
Here are seven of the most frequent error codes you may discover on your Nest thermostat. We’ll explain the basics of each error code on top of how you could address it and the approximate cost to do so. Remember that while the costs will ultimately be dependent on the exact Nest model, you can expect to pay around $75-$200 for repairs. This should also cover travel and labor costs as well as any specific hardware necessary to finish repairs.
e298 – Critical
This critical error code is limited to newer models of the Nest thermostat and shows up when the power is disconnected from the system. Since this is a critical power error, the thermostat will switch to the backup battery system. The error message will remain on the screen until the problem is fixed.
Losing power to your Nest thermostat can be for a number of reasons. The wiring could have disconnected or become damaged, or a disconnection could have happened further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician should inspect electrical connections and wiring until they locate the source of the problem.
e294 – Critical
Critical error code e294 is displayed when your Nest thermostat’s wiring has 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 review the wiring diagram of the thermostat and begin inspecting connectors.
They’ll shut off the power and slowly check each wire, seeing to it that they are fully attached into the connector with the correct amount of bare copper. After they locate the damaged connector, it can be swapped 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 delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will finally power down. Assuming the breakers are on, you can examine a handful of other places before consulting a professional technician.
Because this error can drain your thermostat’s battery, the first step might be restoring enough power to determine if this specific error code is what you’re working with. You can separate the thermostat from its base and provide power with a USB cable. If it displays error code 195, you can continue to visually examine components such as 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 will likely be best to get in touch with a pro.
e103 – Critical
Another critical error code, e103 indicates 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 may 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 determine where the power is surging or why the thermostat is convinced there’s an overcurrent problem.
While this error code isn’t critical, it could still keep 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 receiving sufficient power. You can inspect the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you can get a Nest Power Connector.
With installation of a Nest Power Connector, you may 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 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 excess power is being delivered using the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to protect from electrical damage, it’s a good idea to shut the power off straightaway. You can then get in touch with a professional technician with the necessary experience detecting and resolving electrical problems.
e73 – Critical
When your thermostat displays error code e73, it signifies that the Rc wire is not receiving power.
This will sometimes be as straightforward as the breaker being shut off, but it can also be something with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s a good idea to contact a local professional.