
A Honeywell smart thermostat is a great way to better manage how you use your heating and cooling. But like any technology, you might sometimes experience a problem. With its digital display, Honeywell smart thermostats can show an error code that professional technicians use to understand what's happening. Here are a few of the most likely error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might receive this error code if your home’s Wi-Fi connection did not provide an IP address for the thermostat to connect with. This can take place if your router doesn't complete the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits 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 can complete the DHCP. When it does, you usually also have to power cycle the router and complete the initial setup process again with your thermostat. Doing so should ensure the DHCP is delivered and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed if the password for communicating with your home’s Wi-Fi router is incorrect. When 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 try the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is make sure you’re putting in the correct Wi-Fi password when configuring 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 detected a malfunction. Most often, this occurs when the compressor isn’t working despite being instructed to. But this error code could also appear 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 lead to this error code. And finally, you might 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 turn the thermostat off and on again and error code 40 reappears, it’s best to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat presents error code e43, it can’t communicate with the router, and by extension the 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
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 updated the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor fails, you may notice error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can swap out the sensor and reboot the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where the thermostat is failing to detect a heating or cooling unit. This can mean that the equipment itself is malfunctioning and unable to connect with the thermostat. This can happen when the wiring is defective 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 faulty electrical connection. In situations where the wiring on your specific HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 appear on your Honeywell smart thermostat, it could mean a couple of different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t functioning correctly. Other times, it means the router was disconnected from the outlet before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code stems from sensor failure, a technician will troubleshoot and swap out the affected sensor. If the problem stems from disconnected power, all you’ll have to do is see to it that the router stays on throughout the setup process.