A Honeywell smart thermostat is an easy way to better manage how you use your home comfort system. But like any technology, you may occasionally experience a problem. With its digital display, Honeywell smart thermostats can provide an error code that certified technicians will use to get a better sense of what's happening. Here are several of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can receive this error code when your home’s Wi-Fi connection did not present an IP address for the thermostat to connect to. This can happen if a router doesn't complete 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 resolve error code e42 by making sure that your router has enabled DHCP. When it does, you might 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 delivered and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 is displayed if the password for connecting to your home’s Wi-Fi router is not correct. After 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 to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is verify you’re typing the correct Wi-Fi password when configuring the thermostat.
Honeywell Error Code 40
Error code 40 can show 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 occurs if the compressor isn’t turning on despite being directed to. But this error code can also show up if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by obstructed airflow, can render this error code. And finally, you might see 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 normal operation. If you restart the thermostat and error code 40 reappears, you should try to get in touch with an experienced technician.
Error Code e43 for Honeywell Thermostats
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 the wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reboot 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 give it.
Honeywell Error Code e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you could notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can swap out the sensor and reset the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where the thermostat is unable to recognize a heating or cooling unit. This can mean that the equipment itself is faulty 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 licensed technician can use a voltmeter to assess if there’s a bad electrical connection. When 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 see error code e2 show up on your Honeywell smart thermostat, it can mean several different things. In some cases, one of the sensors responsible for detecting the temperature isn’t operating 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
When the error code is a result of sensor failure, a technician will troubleshoot and replace the impacted sensor. Any time the problem originates from disconnected power, all you’ll have to do is make sure the router remains on during the setup process.