A Honeywell smart thermostat is an easy way to fine-tune how you use your home comfort system. But like any utility, you may sometimes run into a problem. With the digital display, Honeywell smart thermostats can display an error code that certified technicians can use to figure out what's happening. Here are some of the most common error codes you could see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You might receive this error code in the event that your home’s Wi-Fi connection did not provide 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 necessary IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by verifying that your router has enabled DHCP. If it does, you may also have to power cycle the router and repeat the initial setup process with the thermostat. Doing so should ensure the DHCP is delivered and connects to the smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 is displayed if the password for accessing your home’s Wi-Fi router was incorrect. When this error code is displayed for 30 seconds, the thermostat’s digital display will automatically progress 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 solve error e02 is verify you’re putting in the correct Wi-Fi password when configuring the thermostat.
Honeywell Error Code 40
Error code 40 can pop up when the thermostat is notified that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most often, this happens once the compressor isn’t turning on despite being instructed to. But this error code may also appear if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, caused by blocked airflow, can display this error code. And finally, you might 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 examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you reset the thermostat and error code 40 reappears, it’s best to contact an experienced technician.
Error Code e43 for Honeywell Thermostats
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 about 30 seconds. The thermostat might also be disconnected if you’ve recently switched 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 fails, you may notice error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can replace the sensor and restart the thermostat, which should resolve error code e1.
Honeywell Error Code 11n
Error code 11n could appear if the thermostat is unable to recognize a heating or cooling unit. This might mean that the equipment itself is faulty and unable to maintain a connection to the thermostat. This can happen when the wiring is defective or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to find out if there’s a faulty electrical connection. When the wiring on your type of HVAC system is bad, the technician can replace it. When the thermostat itself is the issue, it should probably be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 pop up on your Honeywell smart thermostat, it can mean several different things. Sometimes, one of the sensors that detects the temperature isn’t working like it should. In other cases, it means the router was disconnected from its power source 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 can troubleshoot and replace the damaged sensor. When the problem stems from disconnected power, all you have to do is see to it that the router stays on over the course of the setup process.