A Honeywell smart thermostat is an easy way to optimize how you use your home comfort system. But like any mechanical system, you could occasionally run into a problem. With the digital display, Honeywell smart thermostats can display an error code that professional technicians use to figure out what's going on. Here are several of the most known error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may receive this error code when your home’s Wi-Fi internet did not provide an IP address for the thermostat to hook up to. This can happen if your router does not complete 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 fix error code e42 by making sure that your router has enabled DHCP. Assuming it does, you might also need to power cycle the router and repeat the initial setup process with the 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 whenever the password for communicating with your home’s Wi-Fi router is incorrect. Once 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 resolve error e02 is ensure you’re entering the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can pop up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has identified a malfunction. For the most part, this occurs when the compressor isn’t turning on despite being instructed to. But this error code could also appear if power is disconnected from the outdoor unit for a long period of time. A “High Pressure Fault” error, triggered by blocked airflow, can lead to this error code. And 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 check the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you restart the thermostat and error code 40 reappears, it's time to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This may 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
Restart the router by unplugging it and leaving it that way for around 30 seconds. The thermostat may also be disconnected if you recently updated the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats employ sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you might see 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 reboot 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 connect to a heating or cooling unit. This might mean that the equipment itself is faulty and unable to connect with 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 find out if there’s a bad electrical connection. If the wiring on your specific HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the issue, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 pop up on your Honeywell smart thermostat, it could mean a few different things. For example, one of the sensors responsible for detecting the temperature isn’t functioning properly. In other cases, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code stems from sensor failure, a technician should troubleshoot and replace the damaged sensor. Any time the problem comes from disconnected power, all you’ll have to do is see to it that the router remains on over the course of the setup process.