A Honeywell smart thermostat is a great way to better manage how you use your home comfort system. But like any mechanical system, you might occasionally run into a problem. With its digital display, Honeywell smart thermostats can provide an error code that professional technicians can use to understand what's happening. Here are several of the most likely error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might see this error code if your home’s Wi-Fi connection 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 function automatically transmits the required 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. If it does, you might also need to power cycle the router and perform the setup process again with the thermostat. Completing this task should see to it that the DHCP is sent and connects to your smart thermostat.
Honeywell Error Code e02
Error code e02 occurs whenever the password for communicating with your home’s Wi-Fi router is not correct. 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 attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to resolve error e02 is make sure you’re putting in the correct Wi-Fi password when setting up 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 identified a malfunction. For the most part, this occurs when the compressor isn’t running despite being instructed to. But this error code may also show up if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by poor airflow, can lead to this error code. And finally, you may experience error code 40 if there’s a problem 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, it's time to contact an experienced technician.
Error Code e43 for Honeywell Thermostats
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
Reboot the router by unplugging it and leaving it that way for about 30 seconds. The thermostat might 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 employ sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you may see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can replace the sensor and restart the thermostat, which should clear error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n can appear in situations where the thermostat is failing to recognize a heating or cooling unit. This can mean that the equipment itself is faulty 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 professional technician can use a voltmeter to assess if there’s a faulty electrical connection. In situations where the wiring on your specific HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the issue, it should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 pop up on your Honeywell smart thermostat, it might mean a couple of different things. In some cases, one of the sensors used to detect the temperature isn’t operating properly. Other times, it means the router was disconnected from power before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code is a result of 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 remains on during the setup process.