Installing a Nest thermostat is one of the most convenient 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 properly or at all if you see an error code appear. The precise error code supplies useful information about the source of the problem, something a professional technician can use to provide solutions that much faster.
Let's consider seven of the most likely error codes you could find on your Nest thermostat. We’ll explain the basics of each error code as well as how you can solve it and the projected cost to do so. Remember that while the price will ultimately be dependent on the specific Nest model, you can expect to pay about $75-$200 for repairs. This should include travel and labor costs along with any specific components needed to finish 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 change to the backup battery system. The error message will remain on display 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 could have appeared further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician should check electrical connections and wiring until they find 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 just a software error. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start inspecting connectors.
They’ll shut off the power and slowly look at each wire, making sure they are fully inserted into the connector with the correct amount of bare copper. Once they find the malfunctioning connector, it can be replaced for a new one.
e195 - Critical
This critical error code can surface when the weather outside is severely hot. The HVAC system can shut down and stop sending power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat drains and the thermostat will finally power down. Assuming the breakers are on, you can check a few other places before contacting a professional technician.
As this error can drain your thermostat’s battery, the first step might be providing enough power to figure out if this specific error code is what you’re dealing with. You can separate the thermostat from its base and provide power by using a USB cable. If it reveals error code 195, you should continue to visually check components including 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 contact a pro.
e103 - Critical
Another critical error code, e103 signifies an electrical problem with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing more power than necessary. This may stem from the breaker box, an error from the control board or through a bad connection in the thermostat. Your technician should cautiously investigate and test the Nest’s electrical system to determine where the power is surging or why the thermostat believes there’s an overcurrent problem.
While this error code isn’t critical, it may still prevent you from using the Nest thermostat like normal. Error code n260 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from obtaining adequate 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’ll need a Nest Power Connector.
Due to installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be dealt with 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
Just like error code e103, e104 is a critical error that's the result of an overcurrent. If excessive power is being delivered through the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you notice this error code show up on your Nest thermostat and want to take steps to prevent electrical damage, it’s recommended to switch the power off as soon as you can. You can then get a hold of a professional technician with the appropriate experience identifying and fixing electrical malfunctions.
e73 - Critical
When your thermostat displays error code e73, it signifies that the Rc wire is not getting power. This could be as simple as the breaker being turned off, but it could also be a problem with the wiring. After shutting 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 appears to be out of place, it’s a good idea to contact a local professional.