A Honeywell smart thermostat is an excellent way to fine-tune how you use your HVAC system. But like any technology, you could occasionally experience a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians use to get a better sense of what's happening. Here are a few of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might see this error code in the event that your home’s Wi-Fi internet did not provide an IP address for the thermostat to hook up to. This can occur if your router fails to complete the Dynamic Host Configuration Protocol, or DHCP. This process automatically sends out the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by making sure that your router has enabled DHCP. When it does, you might also need to power cycle the router and repeat the initial setup process with your thermostat. Doing so should see to it that the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed when the password for communicating with your home’s Wi-Fi router was incorrect. Once this error code appears for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to clear error e02 is verify you’re putting in the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can appear when the thermostat is notified that a heat pump or air conditioner’s monitoring system has identified a malfunction. For the most part, this happens once the compressor isn’t turning on despite being instructed to. But this error code could also appear if power is shut off from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by obstructed airflow, can render this error code. And finally, you might see error code 40 if there’s a problem 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 turn the thermostat off and on again and error code 40 reappears, it's time to contact 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 your Wi-Fi. This could 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 updated the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you might notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can replace the sensor and reset the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear when the thermostat can’t recognize a heating or cooling unit. This can mean that the equipment itself is defective and unable to maintain a connection to 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 utilize a voltmeter to find out if there’s a faulty electrical connection. In situations where the wiring on your type of HVAC equipment is bad, the technician can replace it. If the thermostat itself is the issue, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you see error code e2 appear on your Honeywell smart thermostat, it can mean several different things. In some cases, one of the sensors that detects the temperature isn’t operating correctly. In other instances, it means the router was disconnected from its power source before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code stems from sensor failure, a technician should troubleshoot and swap out the damaged sensor. If the problem stems from disconnected power, all you'll need to do is verify the router stays on over the course of the setup process.