A Honeywell smart thermostat is an easy way to fine-tune how you use your HVAC system. But like any mechanical system, you may sometimes run across a problem. With a digital display, Honeywell smart thermostats can display an error code that trained technicians will use to get a better sense of what's going on. Here are some of the most common error codes you may see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You might encounter this error code in the event that your home’s Wi-Fi internet did not provide an IP address for the thermostat to connect with. This can take place if a router does not perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically sends out the necessary IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by verifying that your router has enabled DHCP. If it does, you may also have to power cycle the router and perform the setup process again with your thermostat. This should ensure the DHCP is transmitted and connects to the smart thermostat.
Honeywell Error Code e02
Error code e02 occurs if the password for communicating with your home’s Wi-Fi router was incorrect. After this error code appears for 30 seconds, the thermostat’s digital display will automatically progress 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 make sure you’re entering the correct Wi-Fi password when configuring the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can pop up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this appears when the compressor isn’t turning on despite being instructed to. But this error code may also surface if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by poor airflow, can render this error code. And finally, you could encounter 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 examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you reset the thermostat and error code 40 reappears, you should try to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat presents error code e43, it is unable 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 around 30 seconds. The thermostat could also be disconnected if you recently changed the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Error Code e1
Thermostats utilize sensors to determine the temperature outdoors and indoors. If a sensor fails, you could notice error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can swap out the sensor and reboot the thermostat, which should resolve error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n may appear in situations where the thermostat can’t connect to a heating or cooling unit. This can 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 use a voltmeter to assess if there’s a bad electrical connection. If 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 pop up on your Honeywell smart thermostat, it can mean several different things. For example, one of the sensors used to detect the temperature isn’t working properly. 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
When the error code stems from sensor failure, a technician will troubleshoot and replace the affected sensor. When the problem comes from disconnected power, all you’ll have to do is verify the router stays on throughout the setup process.