A Honeywell smart thermostat is an easy way to optimize how you use your home comfort system. But like any mechanical system, you may sometimes run into a problem. With the digital display, Honeywell smart thermostats can provide an error code that trained technicians use to understand what's going on. Here are a few of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Error Code e42
You might receive this error code if your home’s Wi-Fi connection did not supply an IP address for the thermostat to hook up to. This can occur if your router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically supplies the necessary 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 is enabled for DHCP. Assuming it does, you may also need to power cycle the router and repeat the initial setup process with the thermostat. Doing so should see to it that the DHCP is sent and connects to the smart thermostat.
Honeywell Error Code e02
Error code e02 is displayed if the password for communicating with your home’s Wi-Fi router is incorrect. Once this error code appears 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 clear error e02 is make sure you’re putting in the correct Wi-Fi password when setting up the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can pop up when the thermostat is notified that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this happens once the compressor isn’t turning on despite being directed to. But this error code may also surface if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, induced by blocked airflow, can lead to this error code. And finally, you might 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 inspect the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for regular operation. If you restart the thermostat and error code 40 reappears, it's time to get in touch with an experienced technician.
Error Code e43 for Honeywell Thermostats
If a Honeywell thermostat displays 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
Restart the router by unplugging it and leaving it that way for about 30 seconds. The thermostat might also be disconnected if you’ve 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 utilize sensors to identify the temperature outdoors and indoors. If a sensor malfunctions, you could see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and restart the thermostat, which should take care of error code e1.
Honeywell Error Code 11n
Error code 11n may appear when the thermostat is failing to detect a heating or cooling unit. This can mean that the equipment itself is malfunctioning and unable to connect with the thermostat. This can happen when the wiring is bad or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A licensed technician can use a voltmeter to determine if there’s a bad electrical connection. If the wiring on your existing HVAC equipment is bad, the technician can replace it. When the thermostat itself is the problem, it will likely have to be replaced.
Error Code e2 for Honeywell Thermostats
If you see error code e2 pop up on your Honeywell smart thermostat, it could mean several different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t working like it should. Other times, it means the router was disconnected from its power source before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is caused by sensor failure, a technician will troubleshoot and replace the impacted sensor. When the problem originates from disconnected power, all you'll need to do is see to it that the router remains on over the course of the setup process.
