A Honeywell smart thermostat is an excellent way to better manage how you use your home comfort system. But like any technology, you may sometimes run across a problem. With a digital display, Honeywell smart thermostats can display an error code that certified technicians can use to figure out what's going on. Here are some of the most likely error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can receive this error code in the event that your home’s Wi-Fi connection did not supply an IP address for the thermostat to connect to. This can occur if the router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically supplies the needed 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 can complete the DHCP. Assuming it does, you may also need to power cycle the router and repeat the initial setup process with your thermostat. This should see to it that the DHCP is delivered and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears if the password for accessing your home’s Wi-Fi router is not correct. When 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 to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to solve error e02 is make sure you’re typing the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 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 happens when the compressor isn’t working despite being directed 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, induced by blocked airflow, can display this error code. Lastly, you may see 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 examine 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 best to contact an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat shows error code e43, it is failing 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
Reboot the router by unplugging it and leaving it that way for around 30 seconds. The thermostat may also be disconnected if you’ve recently switched the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats use sensors to determine the temperature outdoors and indoors. If a sensor malfunctions, you may notice error code e1 turn up 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 may appear when the thermostat is unable to connect to a heating or cooling unit. This can mean that the equipment itself is faulty and unable to maintain a connection to 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 professional technician can use a voltmeter to assess if there’s a faulty electrical connection. When the wiring on your type of HVAC equipment is bad, the technician can replace it. If the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 appear on your Honeywell smart thermostat, it might mean several different things. Sometimes, one of the sensors used to detect the temperature isn’t functioning properly. In other cases, it means the router was disconnected from the outlet before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code stems from sensor failure, a technician will troubleshoot and replace the damaged sensor. If the problem stems from disconnected power, all you’ll have to do is make sure the router remains on over the course of the setup process.