How to Resolve These Seven Error Codes on Your Nest Thermostat

Installing a Nest thermostat is one of the most convenient ways to improve the everyday schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make adjustments. But as you can expect, it won’t work correctly or at all if you see an error code on the display. The specific error code offers useful information about the underlying problem, something a knowledgeable technician can use to provide solutions that much quicker.

Let’s consider seven of the most likely error codes you may encounter on your Nest thermostat. We’ll explain the basics of each error code on top of how you can solve it and the projected cost to do so. Remember that while the investment will ultimately hinge on the exact Nest model, you can expect to pay between $75-$200 for repairs. This should include travel and labor costs on top of any specific components needed to complete repairs.

e298 – Critical

This critical error code is limited to newer 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 swap to the backup battery system. The error message will remain on display until the issue is resolved.

Losing power to your Nest thermostat can be for several reasons. The wiring might have disconnected or become damaged, or a disconnection may have occurred further along in your electrical system. This might be the circuit breaker, fuse box or system switch. A knowledgeable technician can inspect electrical connections and wiring until they uncover the source of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring has to be reconfigured. More specifically, you’ll need the technician to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software issue. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start inspecting connectors.

They’ll disconnect the power and gradually look at each wire, making sure they are fully attached into the connector with the correct amount of exposed copper. When they find the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can show up when the weather outside is severely hot. The HVAC system can shut down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat depletes and the thermostat will subsequently power down. Assuming the breakers are on, you can search a handful of other places before calling a professional technician.

Since this error can consume your thermostat’s battery, the first step could be restoring 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 supply power by using a USB cable. In the event it reveals error code 195, you may continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you struggle to find anything wrong with these components, it’s maybe best to call a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical malfunction with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than necessary. This can stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. Your technician should meticulously inspect and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it can still prevent you from using the Nest thermostat like normal. Error code n260 refers to the lack of a C wire or Nest Power Connector, as not having one can block your Nest from obtaining sufficient power. You can examine the Nest’s C connector for the presence of a C wire and modify the wiring itself if there is. If not, you need a Nest Power Connector.

Due to installation of a Nest Power Connector, you may notice error code E297 appear. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 that’s the result of an overcurrent. If excessive power is transported through the Nest’s wiring, it can damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to guard against electrical damage, it’s suggested to switch 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 indicates that the Rc wire is not receiving power.

This will sometimes be as straightforward as the breaker being turned off, but it could also be something with the wiring. After switching off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure nothing is loose or damaged. If nothing looks to be out of place, it’s best to speak with a local professional.