How to Resolve These Seven Error Codes on Your Nest Thermostat

Installing a Nest thermostat is one of the easiest ways to improve the day-to-day schedule of your HVAC system. This smart thermostat can recognize 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 appear. The specific error code offers useful information about the underlying problem, something a trained technician can use to offer solutions that much faster.

Let’s consider seven of the most frequent error codes you might discover on your Nest thermostat. We’ll review the basics of each error code along with how you might address it and the projected cost to do so. Don’t forget that while the price will ultimately depend on the exact Nest model, you can count on paying between $75-$200 for repairs. This should also cover travel and labor costs along with any specific parts 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 detached from the system. Because 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 problem is dealt with.

Losing power to your Nest thermostat can be for a number of reasons. The wiring might have disconnected or become damaged, or a disconnection might have appeared further along in your home’s electrical system. This may be the circuit breaker, fuse box or system switch. A trained technician should inspect 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 should 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 error. If that doesn’t work, they’ll examine the wiring diagram of the thermostat and start looking at connectors.

They’ll disconnect the power and gradually inspect each wire, ensuring they are fully inserted into the connector with the correct amount of bare copper. Once they find the problem connector, it can be swapped for a new one.

e195 – Critical

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

Since this error can drain your thermostat’s battery, the first step may be restoring enough power to figure out if this specific error code is what you’re dealing with. You can detach the thermostat from its base and supply power with a USB cable. Assuming it reveals error code 195, you can continue to visually inspect components such as the wiring as well as your air conditioner’s air filter or drainage system. If you can’t detect anything wrong with these components, it will probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 signifies an electrical malfunction with your Nest thermostat. More specifically, e103 will refer to an overcurrent problem, which means the wiring is receiving more power than needed. This may stem from the breaker box, an error from the control board or thanks to a bad connection in the thermostat. Your technician needs to cautiously investigate and test the Nest’s electrical system to understand where the power is surging or why the thermostat thinks there’s an overcurrent problem.

n260

While this error code isn’t critical, it could still stop 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 getting enough power. You can inspect 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.

With installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be resolved 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 transported inside the Nest’s wiring, it could damage internal components and may even be a fire hazard. If you see this error code show up on your Nest thermostat and want to guard against electrical damage, it’s suggested to switch the power off straightaway. You can then get a hold of a professional technician with the necessary experience diagnosing and fixing electrical damage.

e73 – Critical

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

This may be as simple as the breaker being switched off, but it could also be something with the wiring. After turning 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 appears to be out of place, it’s time to get in touch with a local professional.