Operating a Nest thermostat is one of the best ways to improve the daily schedule of your HVAC system. This smart thermostat can learn your preferences and automatically make changes. But as you may expect, it won’t work properly or at all if you see an error code show up. The specific error code offers useful information about the underlying problem, something a knowledgeable technician can use to offer solutions that much quicker.

Here are seven of the most common error codes you might discover on your Nest thermostat. We’ll walk you through the basics of each error code on top of how you might fix it and the estimated cost to do so. Don’t forget that while the investment 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 hardware 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 detached from the system. Because this is a critical power error, the thermostat will swap to the backup battery system. The error message will remain on the screen until the problem is resolved.

Losing power to your Nest thermostat can be for several reasons. The wiring could have disconnected or become damaged, or a disconnection may have appeared further along in the electrical system. This could be the circuit breaker, fuse box or system switch. A knowledgeable technician should examine electrical connections and wiring until they locate 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 will need to reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not just a software issue. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin checking connectors.

They’ll detach the power and slowly look at each wire, seeing to it that they are fully attached into the connector with the correct amount of exposed copper. When they find 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 severely hot. The HVAC system can break down and stop sending power to your Nest thermostat. When this problem persists, the backup battery in your thermostat drains and the thermostat will finally turn off. In the event the breakers are on, you can examine a few other places before consulting a professional technician.

Since this error can drain your thermostat’s battery, the first step could be restoring enough power to determine if this specific error code is what you’re dealing with. You can detach the thermostat from its base and provide power by using 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 don’t uncover anything wrong with these components, it will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical problem with your Nest thermostat. More specifically, e103 can refer to an overcurrent problem, which means the wiring is receiving more power than needed. This will sometimes stem from the breaker box, an error from the control board or through a defective connection in the thermostat. The technician will cautiously 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.

n260

Even though this error code isn’t critical, it can still prevent you from using the Nest thermostat how you prefer to. Error code n260 refers to the lack of a C wire or Nest Power Connector, as missing one can block your Nest from getting sufficient 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.

During installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be resolved by updating your thermostat in Settings -> Software -> Update. If the Power Connector is already installed, you’ll instead need to update the wiring info in the app from Settings -> Thermostat -> Wiring -> Update wiring.

e104 – Critical

Similar to 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 may even be a fire hazard. If you notice this error code show up on your Nest thermostat and want to protect from electrical damage, it’s recommended to turn the power off as soon as you can. You can then contact a professional technician with the appropriate experience diagnosing and resolving electrical problems.

e73 – Critical

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

This may be as easy as the breaker being switched off, but it may also be an issue with the wiring. After switching 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 time to get in touch with a local professional.