Using a Nest thermostat is one of the easiest ways to optimize the day-to-day schedule of your comfort system. This smart thermostat can be taught 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 exact error code offers useful information about the root of the problem, something a professional technician can use to present solutions that much faster.

Let’s consider seven of the most likely error codes you might discover on your Nest thermostat. We’ll review the basics of each error code along with how you could solve it and the projected cost to do so. Don’t forget that while the costs will ultimately hinge on the precise Nest model, you can anticipate paying between $75-$200 for repairs. This should also cover travel and labor costs along with any specific hardware needed to wrap up 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. As 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 fixed.

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

e294 – Critical

Critical error code e294 is displayed when your Nest thermostat’s wiring has to be reconfigured. More specifically, the technician should reconfigure the R wire. They’ll first complete a factory reset of your thermostat to make sure it’s not simply a software error. If that doesn’t work, they’ll check the wiring diagram of the thermostat and begin looking at connectors.

They’ll shut off the power and gradually inspect each wire, making sure they are fully inserted into the connector with the proper amount of bare copper. Once they find the malfunctioning connector, it can be exchanged for a new one.

e195 – Critical

This critical error code can show up when the weather outside is especially hot. The HVAC system can break down and stop delivering power to your Nest thermostat. When this problem lingers, the backup battery in your thermostat drains and the thermostat will eventually shut down. In the event the breakers are on, you can search a couple of other places before consulting a professional technician.

Since this error can drain your thermostat’s battery, the first step might be providing enough power to determine if this specific error code is what you’re facing. You can detach the thermostat from its base and provide power with a USB cable. In the event it presents error code 195, you should continue to visually inspect components including the wiring as well as your air conditioner’s air filter or drainage system. If you don’t find anything wrong with these components, it will probably be best to call a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical malfunction 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 will sometimes stem from the breaker box, an error from the control board or through a bad connection in the thermostat. The technician should carefully examine and test the Nest’s electrical system to understand where the power is surging or why the thermostat believes there’s an overcurrent problem.

n260

While this error code isn’t critical, it may still stop 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 receiving sufficient 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’ll need a Nest Power Connector.

With installation of a Nest Power Connector, you may notice error code E297 be displayed. This can be remedied 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

Similar to error code e103, e104 is a critical error stemming from an overcurrent. If too much power is sent through the Nest’s wiring, it may damage internal components and could 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 possible. You can then get in touch with a professional technician with the appropriate experience detecting and resolving electrical problems.

e73 – Critical

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

This could be as straightforward as the breaker being switched off, but it could also be a problem with the wiring. After switching off the power to your HVAC system and thermostat, you can visually inspect the wires to make sure none of them are loose or damaged. If nothing appears to be out of place, it’s a good idea to speak with a local professional.