Using a Nest thermostat is one of the most convenient ways to perfect the everyday schedule of your heating and cooling. This smart thermostat can learn your preferences and automatically make improvements. But as you may expect, it won’t work properly or at all if you see an error code show up. The exact error code supplies useful information about the root of the problem, something a trained technician can use to provide solutions that much faster.

Here are seven of the most likely error codes you may discover on your Nest thermostat. We’ll review the basics of each error code along with how you could fix 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 around $75-$200 for repairs. This should also cover travel and labor costs on top of any specific components necessary to complete repairs.

e298 – Critical

This critical error code is limited to newer 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 issue is dealt with.

Losing power to your Nest thermostat can be for a number of reasons. The wiring may have disconnected or become damaged, or a disconnection might have appeared further along in your electrical system. This could be the circuit breaker, fuse box or system switch. A certified technician can examine electrical connections and wiring until they find the root of the problem.

e294 – Critical

Critical error code e294 appears when your Nest thermostat’s wiring needs to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first perform a factory reset of your thermostat to make sure it’s not merely a software error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and begin checking connectors.

They’ll shut off the power and slowly check each wire, making sure they are fully attached into the connector with the correct amount of uncovered copper. Once they locate the malfunctioning connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can appear when the weather outside is severely hot. The HVAC system can fail and stop delivering power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will subsequently power down. Presuming the breakers are on, you can inspect a few other places before consulting a professional technician.

As this error can consume your thermostat’s battery, the first step may be restoring enough power to find out if this specific error code is what you’re facing. You can separate the thermostat from its base and supply power through a USB cable. In the event it presents 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 don’t uncover anything wrong with these components, it will probably be best to get in touch with a pro.

e103 – Critical

Another critical error code, e103 suggests an electrical error with your Nest thermostat. More specifically, e103 can 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 thanks to a defective connection in the thermostat. The technician needs to meticulously examine and test the Nest’s electrical system to figure out 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 concerns the lack of a C wire or Nest Power Connector, as missing one can block your Nest from receiving adequate power. You can inspect the Nest’s C connector for the presence of a C wire and adjust the wiring itself if there is. If not, you need a Nest Power Connector.

During installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be remedied by updating your thermostat in Settings -> Software -> Update. If the Power Connector has already been 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 originating from an overcurrent. If excessive power is being delivered using the Nest’s wiring, it can damage internal components and can even be a fire hazard. If you notice this error code appear on your Nest thermostat and want to guard against electrical damage, it’s a good idea to switch the power off as soon as you can. You can then contact a professional technician with the necessary experience detecting and solving electrical problems.

e73 – Critical

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

This could be as straightforward as the breaker being switched off, but it can 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 they’re not loose or damaged. If nothing looks to be out of place, it’s a good idea to speak with a local professional.