A Honeywell smart thermostat is an excellent way to better manage how you use your HVAC system. But like any mechanical system, you might occasionally run across a problem. With a digital display, Honeywell smart thermostats can provide an error code that certified technicians use to figure out what's going on. Here are some of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Error Code e42
You might receive this error code in the event that 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 does not complete the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the needed IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by verifying that your router has enabled DHCP. When it does, you may also have to power cycle the router and repeat the initial setup process with your thermostat. This should ensure the DHCP is delivered and connects to your smart thermostat.
Honeywell Error Code e02
Error code e02 appears when the password for connecting to your home’s Wi-Fi router is incorrect. When this error code appears for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to resolve error e02 is ensure you’re entering the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 40
Error code 40 can pop up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this appears if the compressor isn’t working despite being directed to. But this error code can also show up if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, caused by blocked airflow, can lead to this error code. Lastly, you could encounter error code 40 if there’s a problem with the refrigerant, 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 regular operation. If you restart the thermostat and error code 40 reappears, it's time to contact an experienced technician.
Error Code e43 for Honeywell Thermostats
If the Honeywell thermostat presents error code e43, it is unable to communicate with the router, and by extension the Wi-Fi. This could 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
Restart the router by unplugging it and leaving it that way for about 30 seconds. The thermostat could also be disconnected if you have recently switched the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you could see error code e1 appear 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 take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear in situations where the thermostat is unable to recognize 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 is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can utilize a voltmeter to assess if there’s a faulty electrical connection. If the wiring on your specific HVAC system is bad, the technician can replace it. If the thermostat itself is the problem, it should probably be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 show up on your Honeywell smart thermostat, it might mean several different things. In some cases, one of the sensors used to detect the temperature isn’t working like it should. In other cases, it means the router was disconnected from the outlet before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is caused by sensor failure, a technician should troubleshoot and swap out the damaged sensor. Any time the problem comes from disconnected power, all you have to do is see to it that the router stays on during the setup process.