A Honeywell smart thermostat is an easy way to fine-tune how you use your heating and cooling. But like any technology, you might occasionally run across a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians will use to get a better sense of what's wrong. Here are some of the most common error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might receive this error code if your home’s Wi-Fi connection did not supply an IP address for the thermostat to connect with. This can happen if your router does not perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically sends out the required IP address for your thermostat to connect to the Wi-Fi.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by making sure that your router has enabled DHCP. When it does, you usually also need to power cycle the router and repeat the initial setup process with your thermostat. This should see to it that the DHCP is sent and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs whenever the password for connecting to your home’s Wi-Fi router was incorrect. Once 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'll need to do to solve error e02 is ensure you’re entering the correct Wi-Fi password when setting up the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can show up when the thermostat is notified that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this occurs when 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, caused by poor airflow, can display this error code. And finally, you might experience error code 40 if there’s something wrong with the coolant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can examine 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 get a hold of an experienced technician.
Honeywell Thermostat Error e43
If your Honeywell thermostat presents error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This might 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
Reboot the router by unplugging it and leaving it that way for about 30 seconds. The thermostat might also be disconnected if you’ve recently switched the password or the Wi-Fi’s SSID, which is the name you provide it.
Error Code e1 for Honeywell Thermostats
Thermostats use sensors to determine the temperature outdoors and indoors. If a sensor fails, you might see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and restart the thermostat, which should take care of error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n can appear when the thermostat is unable to detect a heating or cooling unit. This can mean that the equipment itself is defective and unable to communicate with the thermostat. This can happen when the wiring is defective or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can use a voltmeter to determine if there’s a bad electrical connection. In situations where the wiring on your type of HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the problem, it should probably be replaced.
Honeywell Error Code e2
If you notice error code e2 show up on your Honeywell smart thermostat, it can mean a few different things. In some cases, one of the sensors used to detect the temperature isn’t working like it should. Other times, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code stems from sensor failure, a technician will troubleshoot and replace the affected sensor. Any time the problem originates from disconnected power, all you’ll have to do is verify the router remains on during the setup process.
