How to Resolve These Seven Error Codes on Your Nest Thermostat

Installing a Nest thermostat is one of the easiest ways to optimize the daily schedule of your comfort system. This smart thermostat can be taught your preferences and automatically make adjustments. But as you can expect, it won’t work well or at all if you see an error code appear. The specific error code offers useful information about the underlying problem, something a knowledgeable technician can use to present solutions that much sooner.

Listed below are seven of the most frequent error codes you may find on your Nest thermostat. We’ll review the basics of each error code as well as how you could fix it and the approximate cost to do so. Keep in mind that while the investment will ultimately depend on the precise Nest model, you can count on paying between $75-$200 for repairs. This should also cover travel and labor costs as well as any specific hardware needed to finish repairs.

e298 – Critical

This critical error code is limited to the latest models of the Nest thermostat and is displayed when the power is detached from the system. Since this is a critical power error, the thermostat will change to the backup battery system. The error message will remain on the screen until the issue is resolved.

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

e294 – Critical

Critical error code e294 shows up 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 merely a software issue. If that doesn’t work, they’ll review the wiring diagram of the thermostat and start checking connectors.

They’ll disconnect the power and slowly look at each wire, making sure they are fully attached into the connector with the correct amount of bare copper. Once they find the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can appear when the weather outside is particularly 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 eventually power down. Presuming the breakers are on, you can check a few other places before calling a professional technician.

As this error can deplete your thermostat’s battery, the first step may be providing enough power to find out if this specific error code is what you’re facing. You can detach the thermostat from its base and supply power with a USB cable. In the event it displays error code 195, you should continue to visually inspect components like the wiring as well as your air conditioner’s air filter or drainage system. If you can’t uncover anything wrong with these components, it will likely be best to contact 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 needed. This will sometimes stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. The technician can cautiously examine 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

Although this error code isn’t critical, it might still stop you from using the Nest thermostat how you want to. 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 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 need a Nest Power Connector.

With installation of a Nest Power Connector, you may 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

Similar to error code e103, e104 is a critical error originating from an overcurrent. If excess power is sent using the Nest’s wiring, it could damage internal components and may even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to guard against electrical damage, it’s a good idea to switch the power off as soon as possible. You can then get a hold of a professional technician with the necessary experience identifying and solving electrical problems.

e73 – Critical

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

This will sometimes be as simple as the breaker being turned 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 examine the wires to make sure they’re not loose or damaged. If nothing appears to be out of place, it’s best to get in touch with a local professional.