A Honeywell smart thermostat is a great way to better manage how you use your HVAC system. But like any technology, you might sometimes experience a problem. With the digital display, Honeywell smart thermostats can provide an error code that certified technicians will use to figure out what's going on. Here are a few of the most known error codes you might see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You might receive this error code when your home’s Wi-Fi connection did not supply an IP address for the thermostat to connect with. This can take place if the router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by confirming that your router has enabled DHCP. When it does, you usually also need to power cycle the router and perform the setup process again with your thermostat. Completing this task should see to it that the DHCP is sent and connects to your smart thermostat.
Honeywell Error Code e02
Error code e02 is displayed whenever the password for accessing your home’s Wi-Fi router is incorrect. Once this error code has appeared for 30 seconds, the thermostat’s digital display will automatically progress to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to resolve error e02 is make sure you’re entering the correct Wi-Fi password when setting up the thermostat.
Honeywell Error Code 40
Error code 40 can appear when the thermostat is informed that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most often, this appears once the compressor isn’t working despite being instructed to. But this error code could also show up if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by blocked airflow, can display this error code. Lastly, you might encounter error code 40 if there’s something wrong with the refrigerant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can inspect 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, it's time to contact an experienced technician.
Honeywell Error Code e43
If the Honeywell thermostat shows error code e43, it is unable to communicate with the router, and by extension your Wi-Fi. This could happen if the router’s ethernet cable isn’t plugged in or it isn’t communicating with the wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reset the router by unplugging it and leaving it that way for around 30 seconds. 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 determine the temperature outdoors and indoors. If a sensor fails, you may notice error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and reboot the thermostat, which should clear error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n can appear if the thermostat is failing to recognize a heating or cooling unit. This may mean that the equipment itself is defective and unable to communicate with the thermostat. This sometimes happens when the wiring is defective or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A licensed technician can employ a voltmeter to find out if there’s a faulty electrical connection. When the wiring on your existing HVAC system is bad, the technician can replace it. When the thermostat itself is the issue, 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. Sometimes, one of the sensors that detects the temperature isn’t working properly. In other instances, it means the router was disconnected from its power source before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is a result of sensor failure, a technician can troubleshoot and switch out the affected sensor. Any time the problem originates from disconnected power, all you'll need to do is see to it that the router remains on during the setup process.