A Honeywell smart thermostat is an excellent way to fine-tune how you use your heating and cooling. But like any mechanical system, you might occasionally experience a problem. With the digital display, Honeywell smart thermostats can provide an error code that professional technicians will use to figure out what's going on. Here are some of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may see this error code if your home’s Wi-Fi internet did not present an IP address for the thermostat to connect to. This can happen if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically supplies 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 verifying that your router can complete the DHCP. Assuming it does, you usually also need to power cycle the router and repeat the initial setup process with your thermostat. Doing so should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs if the password for connecting to your home’s Wi-Fi router is not correct. After this error code is displayed 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 have to do to solve error e02 is ensure you’re putting in the correct Wi-Fi password when configuring the thermostat.
Honeywell Error Code 40
Error code 40 can pop up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most often, this occurs once the compressor isn’t running despite being directed to. But this error code can also show up if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by blocked airflow, can display this error code. And finally, you could experience 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 ordinary operation. If you turn the thermostat off and on again and error code 40 reappears, it’s best to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat displays error code e43, it can’t communicate with the router, and by extension your 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
Reboot the router by unplugging it and leaving it that way for a short period. The thermostat could also be disconnected if you’ve recently switched the password or the Wi-Fi’s SSID, which is the name you provide it.
Error Code e1 for Honeywell Thermostats
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor malfunctions, you might see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can replace the sensor and reboot the thermostat, which should resolve error code e1.
Honeywell Error Code 11n
Error code 11n could appear in situations where the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is faulty and unable to connect with the thermostat. This sometimes happens when the wiring is defective or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can use a voltmeter to assess if there’s a faulty electrical connection. In situations where the wiring on your specific HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the problem, it will likely have to be replaced.
Honeywell Error Code e2
If you notice error code e2 pop up on your Honeywell smart thermostat, it can mean a couple of different things. Sometimes, one of the sensors used to detect the temperature isn’t functioning correctly. In other instances, it means the router was disconnected from its power source before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is caused by sensor failure, a technician can troubleshoot and switch out the affected sensor. Any time the problem comes from disconnected power, all you have to do is see to it that the router remains on throughout the setup process.