A Honeywell smart thermostat is a great way to better manage how you use your HVAC system. But like any utility, you might sometimes run across a problem. With the digital display, Honeywell smart thermostats can display an error code that trained technicians can use to understand what's happening. Here are several of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might encounter this error code when your home’s Wi-Fi internet did not provide an IP address for the thermostat to connect with. This can occur if your router fails to execute the Dynamic Host Configuration Protocol, or DHCP. This function automatically supplies the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by making sure that your router is enabled for DHCP. If it does, you might also have 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 occurs if the password for communicating with your home’s Wi-Fi router is incorrect. After 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 need to do to clear 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 show up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most often, this occurs when the compressor isn’t working despite being directed to. But this error code may also surface if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by obstructed airflow, can render this error code. Lastly, you could experience error code 40 if there’s something wrong with the refrigerant, 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 normal operation. If you reset the thermostat and error code 40 reappears, it's time to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat presents error code e43, it is unable to communicate with the router, and by extension your Wi-Fi. This can 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
Reset the router by unplugging it and leaving it that way for about 30 seconds. The thermostat may also be disconnected if you recently changed the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you could notice error code e1 appear 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 clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear in situations where the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is malfunctioning and unable to connect with the thermostat. This can happen when the wiring is bad or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A licensed technician can employ a voltmeter to assess if there’s a poor electrical connection. In situations where the wiring on your existing HVAC equipment is bad, the technician can replace it. If the thermostat itself is the issue, it should probably be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 appear on your Honeywell smart thermostat, it can mean several different things. For example, one of the sensors responsible for detecting the temperature isn’t working correctly. In other instances, it means the router was disconnected from power before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code stems from sensor failure, a technician can troubleshoot and swap out the impacted sensor. When the problem comes from disconnected power, all you have to do is see to it that the router stays on during the setup process.