A Honeywell smart thermostat is an excellent way to better manage how you use your HVAC system. But like any mechanical system, you could occasionally run across a problem. With the digital display, Honeywell smart thermostats can display an error code that trained technicians use to understand what's going on. Here are some of the most common 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 present an IP address for the thermostat to connect with. This can take place if the router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by confirming that your router can complete the DHCP. If it does, you may also have to power cycle the router and complete the initial setup process again with the thermostat. Doing so should ensure the DHCP is delivered and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed whenever the password for connecting to your home’s Wi-Fi router was incorrect. After this error code appears 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 need to do to clear error e02 is make sure you’re entering 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. Most often, this happens once the compressor isn’t running 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 render this error code. Lastly, you might 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 regular operation. If you restart the thermostat and error code 40 reappears, it's time to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If your 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
Reset the router by unplugging it and leaving it that way for around 30 seconds. The thermostat might also be disconnected if you’ve recently changed the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you may see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can change out the sensor and reboot the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear if the thermostat is failing to detect a heating or cooling unit. This might mean that the equipment itself is defective and unable to communicate 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 utilize a voltmeter to find out if there’s a bad electrical connection. In situations where the wiring on your type of HVAC equipment is bad, the technician can replace it. In situations where 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 pop up on your Honeywell smart thermostat, it could mean a couple of different things. For example, one of the sensors that detects the temperature isn’t operating like it should. Other times, it means the router was disconnected from its power source before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is a result of sensor failure, a technician can troubleshoot and replace the damaged sensor. If the problem originates from disconnected power, all you have to do is make sure the router remains on over the course of the setup process.