Using a Nest thermostat is one of the easiest ways to perfect the daily schedule of your heating and cooling. This smart thermostat can recognize your preferences and automatically make improvements. But as you can expect, it won’t work correctly or at all if you see an error code appear. The precise error code provides useful information about the source of the problem, something a professional technician can use to offer solutions that much faster.
Let's consider seven of the most likely error codes you may encounter on your Nest thermostat. We’ll review the basics of each error code along with how you might fix it and the estimated cost to do so. Keep in mind that while the price will ultimately hinge 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 components necessary to complete repairs.
e298 - Critical
This critical error code is limited to the latest models of the Nest thermostat and appears when the power is detached from the system. Because 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 fixed.
Losing power to your Nest thermostat can be for numerous reasons. The wiring could have disconnected or become damaged, or a disconnection may have appeared further along in the electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician should inspect electrical connections and wiring until they uncover the source 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 perform 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 looking at connectors.
They’ll detach the power and gradually check each wire, seeing to it that they are fully inserted into the connector with the correct amount of uncovered copper. After 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 especially hot. The HVAC system can break down and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will subsequently turn off. In the event the breakers are on, you can inspect a few other places before consulting a professional technician.
Since this error can deplete your thermostat’s battery, the first step could be supplying enough power to figure out 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 reveals error code 195, you may continue to visually examine components including the wiring as well as your air conditioner’s air filter or drainage system. If you can't 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 suggests an electrical malfunction with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is experiencing more power than needed. This can stem from the breaker box, an error from the control board or through a faulty connection in the thermostat. A technician can 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.
Although this error code isn’t critical, it can still prevent you from using the Nest thermostat how you want to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as not having one can block your Nest from getting adequate power. You can check the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you can get a Nest Power Connector.
Due to installation of a Nest Power Connector, you will sometimes notice error code E297 be displayed. 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
Like error code e103, e104 is a critical error stemming from an overcurrent. If excessive power is sent through 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 guard against electrical damage, it’s recommended to turn the power off as soon as possible. You can then get a hold of a professional technician with the proper experience detecting and resolving electrical issues.
e73 - Critical
When your thermostat displays error code e73, it indicates that the Rc wire is not receiving power. This might be as easy as the breaker being shut off, but it could 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 seems to be out of place, it’s best to contact a local professional.