A Honeywell smart thermostat is an excellent way to fine-tune how you use your HVAC system. But like any utility, you could sometimes run across a problem. With its digital display, Honeywell smart thermostats can display an error code that certified technicians will use to get a better sense of what's going on. Here are several of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can encounter this error code if your home’s Wi-Fi internet did not provide an IP address for the thermostat to connect to. This can take place if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically sends out the necessary IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by confirming that your router has enabled DHCP. Assuming it does, you may also need to power cycle the router and complete the initial setup process again with your thermostat. Doing so should ensure the DHCP is delivered and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed when the password for communicating with your home’s Wi-Fi router was 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 try the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to solve error e02 is make sure you’re putting in the correct Wi-Fi password when setting up 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 occurs once the compressor isn’t turning on despite being instructed to. But this error code can also surface if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, induced by blocked airflow, can render this error code. And finally, you may 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 regular operation. If you reset the thermostat and error code 40 reappears, you should try to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents error code e43, it is unable 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 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 could also be disconnected if you recently updated the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor fails, you may see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can swap out the sensor and reboot the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear in situations where the thermostat can’t connect to a heating or cooling unit. This can mean that the equipment itself is faulty and unable to connect with the thermostat. This sometimes happens when the wiring is damaged or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can use a voltmeter to find out if there’s a bad electrical connection. When the wiring on your existing HVAC system is bad, the technician can replace it. When the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 appear on your Honeywell smart thermostat, it can mean several different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t working correctly. In other instances, it means the router was disconnected from its power source before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code is caused by sensor failure, a technician will troubleshoot and replace the impacted sensor. When the problem comes from disconnected power, all you'll need to do is see to it that the router remains on throughout the setup process.