A Honeywell smart thermostat is an easy way to optimize how you use your HVAC system. 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 can use to get a better sense of what's happening. Here are some of the most known error codes you may see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You may receive this error code if your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect to. This can occur if your router fails to execute the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically transmits the necessary 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 can complete the DHCP. Assuming it does, you might also have to power cycle the router and complete the initial setup process again with your thermostat. Completing this task should ensure the DHCP is delivered and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 occurs if 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 attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to solve error e02 is ensure you’re entering the correct Wi-Fi password when configuring 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 detected a malfunction. Most often, this appears if the compressor isn’t working despite being instructed to. But this error code can also appear if power is shut off from the outdoor unit for a long period of time. A “High Pressure Fault” error, triggered by obstructed airflow, can render this error code. Finally, you may encounter error code 40 if there’s an issue 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 regular operation. If you turn the thermostat off and on again and error code 40 reappears, you should try to get a hold of an experienced technician.
Honeywell Error Code e43
If your Honeywell thermostat presents 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 the wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reset the router by unplugging it and leaving it that way for about 30 seconds. The thermostat may also be disconnected if you have recently updated the password or the Wi-Fi’s SSID, which is the name you create for it.
Error Code e1 for Honeywell Thermostats
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you may notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can change out the sensor and reboot the thermostat, which should clear error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n could appear when the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is malfunctioning and unable to maintain a connection to the thermostat. This can happen 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 determine if there’s a faulty 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 issue, it should probably be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 pop up on your Honeywell smart thermostat, it might mean a few different things. For example, one of the sensors that detects the temperature isn’t working like it should. In other instances, it means the router was disconnected from the outlet before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is caused by sensor failure, a technician should troubleshoot and replace the damaged sensor. If the problem comes from disconnected power, all you’ll have to do is see to it that the router remains on throughout the setup process.
