A Honeywell smart thermostat is an excellent way to better manage how you use your heating and cooling. But like any utility, you might occasionally run into a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians can use to figure out what's going on. Here are several of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may receive this error code in the event that your home’s Wi-Fi internet did not present an IP address for the thermostat to connect with. This can take place if your router does not perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically transmits the required IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by making sure that your router has enabled DHCP. Assuming it does, you may also need to power cycle the router and repeat the initial setup process with your thermostat. Completing this task should ensure the DHCP is transmitted and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed if the password for connecting to your home’s Wi-Fi router was incorrect. Once this error code has appeared for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to clear error e02 is verify you’re putting in the correct Wi-Fi password when configuring 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. Most commonly, this appears if the compressor isn’t running despite being instructed to. But this error code can also surface if power is disconnected from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, triggered by blocked airflow, can render this error code. Finally, you might encounter error code 40 if there’s a problem with the coolant, 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 turn the thermostat off and on again and error code 40 reappears, it's time to contact 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 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
Reboot the router by unplugging it and leaving it that way for a short period. The thermostat may also be disconnected if you have recently changed the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Thermostat Error e1
Thermostats employ sensors to detect the temperature outdoors and indoors. If a sensor fails, 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.
Honeywell Thermostat Error 11n
Error code 11n can appear when the thermostat is failing to recognize a heating or cooling unit. This may mean that the equipment itself is defective and unable to maintain a connection to the thermostat. This can happen when the wiring is bad or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A licensed technician can use a voltmeter to determine if there’s a faulty electrical connection. When the wiring on your existing HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the source of the error code, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you see error code e2 pop up on your Honeywell smart thermostat, it might mean a couple of different things. For example, 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
If the error code is caused by sensor failure, a technician can troubleshoot and switch out the affected sensor. When the problem comes from disconnected power, all you’ll have to do is see to it that the router remains on during the setup process.