Operating a Nest thermostat is one of the most convenient ways to optimize the daily schedule of your comfort system. This smart thermostat can learn your preferences and automatically make adjustments. But as you might expect, it won’t work properly or at all if you see an error code on the display. The specific error code supplies useful information about the underlying problem, something a knowledgeable technician can use to provide solutions that much sooner.

Let’s consider seven of the most frequent error codes you may find on your Nest thermostat. We’ll explain the basics of each error code as well as how you might fix it and the projected cost to do so. Remember that while the investment will ultimately be dependent 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 hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and appears when the power is shut off. 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 a number of reasons. The wiring may have disconnected or become damaged, or a disconnection may have occurred further along in your home’s electrical system. This might be the circuit breaker, fuse box or system switch. A professional technician can examine electrical connections and wiring until they find the source of the problem.

e294 – Critical

Critical error code e294 appears 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 simply a software problem. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin looking at connectors.

They’ll detach the power and slowly check each wire, seeing to it that they are fully placed into the connector with the proper amount of bare copper. Once they locate the problem connector, it can be swapped for a new one.

e195 – Critical

This critical error code can appear when the weather outside is especially hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem lasts, the backup battery in your thermostat depletes and the thermostat will eventually power down. In the event the breakers are on, you can inspect a handful of other places before contacting a professional technician.

As this error can consume your thermostat’s battery, the first step might be restoring enough power to find out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and provide power through a USB cable. If it reveals error code 195, you should continue to visually examine components including 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 will likely be best to call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical error with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is getting more power than what is safe and normal. This can stem from the breaker box, an error from the control board or through a defective connection in the thermostat. A technician will carefully inspect and test the Nest’s electrical system to figure out where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

Even though this error code isn’t critical, it may 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 missing one can block your Nest from getting enough power. You can examine 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 might notice error code E297 appear. 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 originating from an overcurrent. If excessive power is being delivered through the Nest’s wiring, it can damage internal components and can even be a fire hazard. If you notice this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off as soon as you can. You can then contact a professional technician with the appropriate experience diagnosing and fixing electrical problems.

e73 – Critical

When your thermostat displays error code e73, it indicates that the Rc wire is not getting power.

This might be as simple as the breaker being switched 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 check the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s time to contact a local professional.