A Honeywell smart thermostat is a great way to fine-tune how you use your home comfort system. But like any mechanical system, you might sometimes experience a problem. With a digital display, Honeywell smart thermostats can show an error code that professional technicians use to understand what's wrong. Here are some of the most likely error codes you could 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 present an IP address for the thermostat to connect with. This can occur if your router fails to execute the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically transmits the required IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by verifying that your router has enabled DHCP. When it does, you usually also have to power cycle the router and complete the initial setup process again with the thermostat. This should ensure the DHCP is transmitted and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears if the password for connecting to your home’s Wi-Fi router is not correct. 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 solve error e02 is verify you’re typing the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can appear when the thermostat is informed that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most commonly, this happens if the compressor isn’t working despite being instructed to. But this error code could also appear if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, induced by poor airflow, can display this error code. Finally, you may 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 check the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you turn the thermostat off and on again and error code 40 reappears, it's time to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If the 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 the wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Restart the router by unplugging it and leaving it that way for around 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 give it.
Honeywell Thermostat Error e1
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you may notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can replace the sensor and reset the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where the thermostat is unable to recognize a heating or cooling unit. This can mean that the equipment itself is malfunctioning 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 professional technician can utilize a voltmeter to find out if there’s a bad electrical connection. When the wiring on your type of HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the problem, it should probably be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 show up on your Honeywell smart thermostat, it could mean a few different things. Sometimes, one of the sensors that detects the temperature isn’t functioning properly. 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 will troubleshoot and switch out the damaged sensor. When the problem stems from disconnected power, all you have to do is make sure the router remains on throughout the setup process.