A Honeywell smart thermostat is an easy way to better manage how you use your heating and cooling. But like any technology, you could occasionally run across a problem. With its digital display, Honeywell smart thermostats can display an error code that trained technicians will use to get a better sense of what's happening. Here are a few of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might see this error code in the event that your home’s Wi-Fi connection did not present an IP address for the thermostat to connect to. This can occur if a router does not perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically supplies the needed IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by verifying that your router can complete the DHCP. If it does, you may also need to power cycle the router and complete the initial setup process again with the thermostat. Completing this task should ensure the DHCP is sent and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed whenever the password for connecting to your home’s Wi-Fi router is not correct. Once this error code appears for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is make sure you’re entering the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 40
Error code 40 can show up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has identified a malfunction. For the most part, this happens when the compressor isn’t turning on 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, caused by poor airflow, can lead to this error code. Lastly, 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 turn the thermostat off and on again and error code 40 reappears, you should try to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If your Honeywell thermostat displays error code e43, it can’t communicate with the router, and by extension your Wi-Fi. This might 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’ve recently changed the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor fails, you might see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and reboot the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear if the thermostat is failing to detect a heating or cooling unit. This may mean that the equipment itself is faulty and unable to connect 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 licensed technician can utilize a voltmeter to assess 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. When the thermostat itself is the source of the error code, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 show up on your Honeywell smart thermostat, it could mean a few different things. For example, one of the sensors that detects the temperature isn’t operating properly. In other cases, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is a result of sensor failure, a technician can troubleshoot and swap out the affected sensor. When the problem originates from disconnected power, all you have to do is verify the router stays on during the setup process.