A Honeywell smart thermostat is an excellent way to optimize how you use your home comfort system. But like any utility, you could sometimes experience a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians can use to understand what's happening. Here are some of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may see this error code in the event that your home’s Wi-Fi connection did not supply 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 function automatically supplies the necessary 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 is enabled for DHCP. When it does, you might also need to power cycle the router and repeat the initial setup process with the thermostat. Doing so should ensure the DHCP is sent and connects to the smart thermostat.
Honeywell Error Code e02
Error code e02 appears if the password for communicating with your home’s Wi-Fi router is incorrect. Once this error code has appeared 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 need to do to clear error e02 is verify you’re entering the correct Wi-Fi password when configuring the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can show up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this occurs once the compressor isn’t turning on despite being directed 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 obstructed airflow, can display this error code. And finally, you might encounter error code 40 if there’s something wrong with the coolant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for regular operation. If you restart the thermostat and error code 40 reappears, you should try to contact an experienced technician.
Honeywell Error Code e43
If a Honeywell thermostat presents error code e43, it is unable to communicate with the router, and by extension the 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
Reset the router by unplugging it and leaving it that way for a short period. The thermostat could also be disconnected if you have recently switched the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to determine the temperature outdoors and indoors. If a sensor fails, you could see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can swap out the sensor and restart the thermostat, which should take care of error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n could appear in situations where the thermostat is unable to connect to a heating or cooling unit. This can mean that the equipment itself is malfunctioning and unable to maintain a connection to the thermostat. This sometimes happens when the wiring is defective or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A licensed technician can utilize a voltmeter to assess if there’s a bad 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 source of the error code, it should probably be replaced.
Error Code e2 for Honeywell Thermostats
If you’ve noticed error code e2 show up on your Honeywell smart thermostat, it could mean several different things. In some cases, one of the sensors that detects the temperature isn’t functioning properly. In other instances, it means the router was disconnected from power 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 should troubleshoot and switch out the damaged sensor. When the problem originates from disconnected power, all you have to do is verify the router remains on during the setup process.