A Honeywell smart thermostat is a great way to fine-tune how you use your HVAC system. But like any technology, you might occasionally experience a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians will use to figure out what's happening. Here are a few of the most known error codes you could see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You can encounter this error code when your home’s Wi-Fi internet did not present an IP address for the thermostat to connect to. This can occur if your router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically sends out the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by making sure that your router has enabled DHCP. When it does, you usually also have to power cycle the router and repeat the initial setup process with your thermostat. Completing this task should see to it that the DHCP is transmitted and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 occurs whenever the password for connecting to your home’s Wi-Fi router is incorrect. When 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'll need to do to resolve error e02 is ensure you’re putting in the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can appear 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 if the compressor isn’t working despite being directed to. But this error code may also show up if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by poor airflow, can display this error code. Lastly, you could encounter error code 40 if there’s something wrong with the coolant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can check 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, it's time to contact 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 may 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 may also be disconnected if you have recently updated the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Error Code e1
Thermostats utilize sensors to detect the temperature outdoors and indoors. If a sensor breaks down, you might notice error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can swap out the sensor and restart the thermostat, which should resolve error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n may appear if the thermostat is failing to recognize a heating or cooling unit. This might mean that the equipment itself is malfunctioning 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 qualified technician can use a voltmeter to determine if there’s a bad electrical connection. In situations where the wiring on your specific 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 Error Code e2
If you see error code e2 appear on your Honeywell smart thermostat, it could mean several different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t functioning correctly. In other cases, it means the router was disconnected from the outlet before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code stems from sensor failure, a technician can troubleshoot and switch out the impacted sensor. Any time the problem comes from disconnected power, all you’ll have to do is see to it that the router remains on throughout the setup process.