A Honeywell smart thermostat is an easy way to fine-tune how you use your home comfort system. But like any technology, you may sometimes run across a problem. With its digital display, Honeywell smart thermostats can display an error code that trained technicians will use to understand what's wrong. Here are a few of the most known error codes you may see on your Honeywell smart thermostat.
Error Code e42 for Honeywell Thermostats
You can receive this error code when your home’s Wi-Fi internet did not provide an IP address for the thermostat to connect to. This can occur if a router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically transmits the needed IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by verifying that your router has enabled DHCP. If it does, you might also need to power cycle the router and perform the setup process again with your thermostat. Doing so should ensure the DHCP is transmitted and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 is displayed whenever the password for connecting to your home’s Wi-Fi router was incorrect. When this error code is displayed for 30 seconds, the thermostat’s digital display automatically transitions 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 make sure you’re putting in the correct Wi-Fi password when setting up the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can pop up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most often, this occurs once the compressor isn’t running despite being instructed to. But this error code may also surface if power is shut off from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by blocked airflow, can display this error code. Finally, you may 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 restart the thermostat and error code 40 reappears, it's time to get in touch with an experienced technician.
Error Code e43 for Honeywell Thermostats
If the Honeywell thermostat presents error code e43, it is unable to communicate with the router, and by extension your Wi-Fi. This might 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.
Error Code e1 for Honeywell Thermostats
Thermostats use sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you could see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can replace the sensor and reboot the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear if the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is malfunctioning and unable to maintain a connection to 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 assess if there’s a poor electrical connection. When the wiring on your specific HVAC equipment is bad, the technician can replace it. If the thermostat itself is the problem, it should probably be replaced.
Error Code e2 for Honeywell Thermostats
If you notice error code e2 appear on your Honeywell smart thermostat, it might mean a couple of different things. In some cases, one of the sensors that detects the temperature isn’t operating correctly. In other cases, it means the router was disconnected from the outlet before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is caused by sensor failure, a technician will troubleshoot and switch out the affected sensor. If the problem stems from disconnected power, all you’ll have to do is make sure the router stays on during the setup process.