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 adjustments. But as you might expect, it won’t work well or at all if you see an error code appear. The precise error code offers useful information about the root of the problem, something a knowledgeable technician can use to present solutions that much quicker.
Let's consider seven of the most likely error codes you may find on your Nest thermostat. We’ll explain the basics of each error code along with how you can solve it and the approximate cost to do so. Remember that while the costs will ultimately hinge on the precise Nest model, you can anticipate paying between $75-$200 for repairs. This should include travel and labor costs as well as any specific parts necessary 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. 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 problem is fixed.
Losing power to your Nest thermostat can be for numerous reasons. The wiring might have disconnected or become damaged, or a disconnection could have appeared further along in your home's electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician will examine electrical connections and wiring until they find 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, the technician should 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 check the wiring diagram of the thermostat and start inspecting 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 proper amount of uncovered copper. Once they pinpoint the problem connector, it can be replaced for a new one.
e195 - Critical
This critical error code can show up when the weather outside is particularly hot. The HVAC system can shut down and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will eventually turn off. Presuming the breakers are on, you can inspect a handful of other places before consulting a professional technician.
Because this error can deplete your thermostat’s battery, the first step may be supplying enough power to find out if this specific error code is what you’re facing. You can separate the thermostat from its base and provide power through a USB cable. Assuming it reveals error code 195, you can continue to visually examine components like the wiring as well as your air conditioner’s air filter or drainage system. If you can't detect anything wrong with these components, it will likely be best to get in touch with a pro.
e103 - Critical
Another critical error code, e103 signifies an electrical problem with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is getting 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. Your technician can carefully examine 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.
Even though this error code isn’t critical, it can still keep you from using the Nest thermostat like normal. 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 obtaining enough 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 can get a Nest Power Connector.
Due to 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 was already installed, you’ll instead have 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 that's the result of an overcurrent. If excessive power is being delivered inside the Nest’s wiring, it could damage internal components and can even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s a good idea to shut the power off as soon as you can. You can then contact a professional technician with the necessary experience identifying and solving electrical damage.
e73 - Critical
When your thermostat displays error code e73, it signifies that the Rc wire is not getting power. This might be as easy as the breaker being shut off, but it can also be an issue with the wiring. After switching 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.