A Honeywell smart thermostat is an easy way to optimize how you use your HVAC system. But like any mechanical system, you may sometimes run into a problem. With its digital display, Honeywell smart thermostats can display an error code that professional technicians can use to figure out what's wrong. Here are some of the most likely error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might encounter this error code when your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect with. This can occur if a router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically sends out the needed 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 is enabled for DHCP. If it does, you might also need to power cycle the router and repeat the initial setup process with the thermostat. Doing so should see to it that the DHCP is transmitted and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed if the password for accessing your home’s Wi-Fi router is not correct. After 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 try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to resolve error e02 is make sure you’re typing the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can show up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this happens if the compressor isn’t turning on despite being instructed to. But this error code may also appear if power is disconnected from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, induced by poor airflow, can display this error code. Lastly, you could encounter 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 restart the thermostat and error code 40 reappears, you should try to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If your Honeywell thermostat presents error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This might 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 about 30 seconds. The thermostat may also be disconnected if you’ve recently changed the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats employ sensors to determine the temperature outdoors and indoors. If a sensor malfunctions, you could see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can swap out the sensor and restart the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear when the thermostat is unable to recognize a heating or cooling unit. This might mean that the equipment itself is faulty and unable to connect with the thermostat. This sometimes happens when the wiring is damaged or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can employ 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 will likely have to be replaced.
Honeywell Thermostat Error e2
If you see error code e2 pop up on your Honeywell smart thermostat, it could mean a couple of different things. For example, one of the sensors used to detect the temperature isn’t functioning correctly. In other instances, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code stems from sensor failure, a technician should troubleshoot and replace the damaged sensor. Any time the problem stems from disconnected power, all you have to do is verify the router stays on during the setup process.