A Honeywell smart thermostat is an easy way to better manage how you use your heating and cooling. But like any technology, you may occasionally experience a problem. With the digital display, Honeywell smart thermostats can provide an error code that professional technicians will use to figure out what's wrong. Here are several of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Error Code e42
You might receive this error code in the event that your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect with. This can happen if the router does not execute the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically sends out the necessary IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by verifying that your router has enabled DHCP. If it does, you usually also have to power cycle the router and perform the setup process again with the thermostat. Completing this task should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed whenever the password for connecting to your home’s Wi-Fi router is 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 try the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is verify you’re typing the correct Wi-Fi password when configuring the thermostat.
Honeywell Error Code 40
Error code 40 can pop up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most often, this occurs if the compressor isn’t running despite being instructed to. But this error code could also surface if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, induced by obstructed airflow, can render this error code. And finally, you could see 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 regular operation. If you turn the thermostat off and on again and error code 40 reappears, it’s best to get a hold of an experienced technician.
Honeywell Error Code e43
If the Honeywell thermostat shows error code e43, it is unable 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 your wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reboot the router by unplugging it and leaving it that way for a short period. The thermostat could also be disconnected if you recently switched 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 detect the temperature outdoors and indoors. If a sensor breaks down, you may notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can change out the sensor and restart the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is defective and unable to connect 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 qualified technician can utilize a voltmeter to assess if there’s a poor electrical connection. When the wiring on your type of HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the source of the error code, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you see error code e2 show 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 instances, it means the router was disconnected from the outlet before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where 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 need to do is make sure the router stays on during the setup process.