A Honeywell smart thermostat is an easy way to better manage how you use your HVAC system. But like any utility, you might occasionally run into a problem. With the digital display, Honeywell smart thermostats can display an error code that professional technicians will use to understand what's wrong. Here are some of the most known error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can encounter this error code in the event that your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect to. This can happen if the router fails to complete the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically transmits 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 verifying that your router has enabled DHCP. When it does, you usually also have to power cycle the router and perform the setup process again with the thermostat. Completing this task should ensure the DHCP is delivered and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs when the password for connecting to your home’s Wi-Fi router is incorrect. After this error code has appeared for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to solve error e02 is make sure you’re typing 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 happens if the compressor isn’t working despite being instructed to. But this error code could also surface if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, triggered by poor airflow, can lead to this error code. Finally, you may see 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 check the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you restart the thermostat and error code 40 reappears, it’s best to contact an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This may 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
Reset the router by unplugging it and leaving it that way for about 30 seconds. The thermostat may also be disconnected if you’ve recently updated the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats employ sensors to detect the temperature outdoors and indoors. If a sensor breaks down, you may see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can change out the sensor and reset the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear in situations where the thermostat is unable to connect to a heating or cooling unit. This may mean that the equipment itself is faulty and unable to communicate with the thermostat. This sometimes happens when the wiring is damaged or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to determine if there’s a bad electrical connection. If the wiring on your existing HVAC system is bad, the technician can replace it. If 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 used to detect the temperature isn’t working correctly. 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
If the error code stems from sensor failure, a technician will troubleshoot and replace the affected sensor. If the problem originates from disconnected power, all you’ll have to do is make sure the router stays on over the course of the setup process.