How to Resolve These Seven Error Codes on Your Nest Thermostat

Installing a Nest thermostat is one of the easiest 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 well or at all if you see an error code on the display. The exact error code offers useful information about the source of the problem, something a trained technician can use to offer solutions that much quicker.

Listed below are seven of the most likely error codes you may find on your Nest thermostat. We’ll review the basics of each error code on top of how you can address it and the projected cost to do so. Remember that while the investment will ultimately be dependent on the exact Nest model, you can expect to pay about $75-$200 for repairs. This should also cover travel and labor costs as well as any specific hardware needed to complete repairs.

e298 – Critical

This critical error code is limited to new models of the Nest thermostat and is displayed when the power is disconnected 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 fixed.

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

e294 – Critical

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

They’ll shut off the power and progressively check each wire, making sure they are fully placed into the connector with the correct amount of bare copper. When they pinpoint the damaged connector, it can be replaced for a new one.

e195 – Critical

This critical error code can show up when the weather outside is particularly hot. The HVAC system can break down and stop giving power to your Nest thermostat. When this problem persists, the backup battery in your thermostat depletes and the thermostat will subsequently shut down. In the event the breakers are on, you can examine a few other places before calling a professional technician.

Because this error can deplete 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 separate the thermostat from its base and deliver power through a USB cable. Assuming it reveals 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 struggle to uncover anything wrong with these components, it will probably be best to contact a pro.

e103 – Critical

Another critical error code, e103 indicates an electrical malfunction with your Nest thermostat. More specifically, e103 may refer to an overcurrent problem, which means the wiring is experiencing more power than what is safe and normal. This can stem from the breaker box, an error from the control board or because of a bad connection in the thermostat. A technician will cautiously investigate and test the Nest’s electrical system to determine 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 may still keep you from using the Nest thermostat how you want to. Error code n260 concerns the lack of a C wire or Nest Power Connector, as the absence of one can block your Nest from receiving adequate power. You can check 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.

During installation of a Nest Power Connector, you will sometimes notice error code E297 show up. This can be dealt with 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

Just like error code e103, e104 is a critical error originating from an overcurrent. If too much power is being delivered using the Nest’s wiring, it may damage internal components and could even be a fire hazard. If you see this error code pop up on your Nest thermostat and want to protect from electrical damage, it’s suggested to turn the power off as soon as you can. 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 might 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 inspect the wires to make sure none of them are loose or damaged. If nothing looks to be out of place, it’s a good idea to contact a local professional.