Using a Nest thermostat is one of the most convenient ways to improve the day-to-day schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make changes. But as you may expect, it won’t work well or at all if you see an error code appear. The exact error code provides useful information about the root of the problem, something a professional technician can use to offer solutions that much faster.
Here are seven of the most likely error codes you may encounter on your Nest thermostat. We’ll review the basics of each error code on top of how you could address it and the projected cost to do so. Keep in mind that while the investment will ultimately depend on the exact Nest model, you can anticipate paying between $75-$200 for repairs. This should include travel and labor costs on top of any specific parts needed to wrap up repairs.
e298 – Critical
This critical error code is limited to the latest models of the Nest thermostat and is displayed 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 continue to be displayed until the problem is resolved.
Losing power to your Nest thermostat can be for numerous reasons. The wiring may have disconnected or become damaged, or a disconnection may have occurred further along in the 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 root of the problem.
e294 – Critical
Critical error code e294 is displayed when your Nest thermostat’s wiring should be reconfigured. More specifically, the technician will need to reconfigure the R wire. They’ll first conduct a factory reset of your thermostat to make sure it’s not just a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start looking at connectors.
They’ll shut off the power and slowly check each wire, seeing to it that they are fully inserted into the connector with the correct amount of uncovered copper. Once they locate the damaged connector, it can be exchanged for a new one.
e195 – Critical
This critical error code can appear when the weather outside is particularly hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will finally power down. Presuming the breakers are on, you can examine a handful of other places before consulting a professional technician.
As this error can deplete your thermostat’s battery, the first step may be restoring enough power to determine 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. 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 don’t find anything wrong with these components, it’s maybe best to contact 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 will sometimes stem from the breaker box, an error from the control board or through a defective connection in the thermostat. The technician can carefully examine and test the Nest’s electrical system to determine where the power is surging or why the thermostat thinks there’s an overcurrent problem.
While this error code isn’t critical, it might still keep 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 not having one can block your Nest from getting adequate power. You can inspect 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.
Due to 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 was already installed, you’ll instead have 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 stemming from an overcurrent. If excessive power is transported using the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to take steps to prevent electrical damage, it’s a good idea to switch the power off as soon as you can. You can then get a hold of a professional technician with the appropriate experience detecting and solving electrical malfunctions.
e73 – Critical
When your thermostat displays error code e73, it indicates that the Rc wire is not receiving power.
This may be as easy as the breaker being turned off, but it can also be an issue with the wiring. After shutting off the power to your HVAC system and thermostat, you can visually check the wires to make sure nothing is loose or damaged. If nothing seems to be out of place, it’s time to speak with a local professional.