A Honeywell smart thermostat is a great way to better manage how you use your heating and cooling. But like any utility, you may occasionally experience a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians will use to understand what's going on. Here are some of the most likely error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may receive this error code in the event that your home’s Wi-Fi connection did not provide an IP address for the thermostat to connect with. This can happen if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically transmits the required IP address for your thermostat to connect to the Wi-Fi.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by making sure that your router has enabled DHCP. When it does, you might also need to power cycle the router and repeat the initial setup process with your thermostat. Doing so should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears whenever the password for accessing your home’s Wi-Fi router was incorrect. After this error code appears for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to resolve error e02 is make sure you’re typing the correct Wi-Fi password when setting up the thermostat.
Honeywell Error Code 40
Error code 40 can appear when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this occurs once the compressor isn’t running despite being directed to. But this error code can also show up if power is disconnected from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by obstructed airflow, can lead to this error code. And finally, you may experience error code 40 if there’s an issue with the coolant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can check the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for ordinary operation. If you restart the thermostat and error code 40 reappears, you should try to contact an experienced technician.
Honeywell Error Code e43
If your Honeywell thermostat displays error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This can happen if the router’s ethernet cable isn’t plugged in or it isn’t communicating with your wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reboot the router by unplugging it and leaving it that way for a short period. The thermostat might also be disconnected if you have recently switched the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Error Code e1
Thermostats employ sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you might see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can replace the sensor and reset the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear when the thermostat can’t connect to a heating or cooling unit. This might mean that the equipment itself is malfunctioning and unable to communicate with the thermostat. This sometimes happens when the wiring is bad or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can employ a voltmeter to assess if there’s a bad electrical connection. If the wiring on your specific HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the source of the error code, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you see error code e2 show up on your Honeywell smart thermostat, it could mean several different things. For example, one of the sensors responsible for detecting the temperature isn’t functioning like it should. Other times, it means the router was disconnected from power before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code stems from sensor failure, a technician should troubleshoot and switch out the affected sensor. When the problem comes from disconnected power, all you’ll have to do is see to it that the router stays on throughout the setup process.
