A Honeywell smart thermostat is a great way to fine-tune how you use your heating and cooling. But like any technology, you could sometimes experience a problem. With a digital display, Honeywell smart thermostats can show an error code that trained technicians use to understand what's wrong. Here are several of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can see this error code in the event that your home’s Wi-Fi connection did not provide an IP address for the thermostat to connect with. This can occur if a router doesn't execute the Dynamic Host Configuration Protocol, or DHCP. This process automatically transmits the needed IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by confirming that your router is enabled for DHCP. Assuming it does, you may also need to power cycle the router and complete the initial setup process again with your thermostat. Doing so should see to it that the DHCP is delivered and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed if the password for connecting to your home’s Wi-Fi router is not correct. After this error code appears for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to resolve error e02 is ensure you’re putting in the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can show 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 working despite being instructed to. But this error code can also appear if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, induced by obstructed airflow, can display this error code. Finally, you might experience 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 check 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 the Honeywell thermostat shows error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This may 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
Reboot 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 give it.
Honeywell Thermostat Error e1
Thermostats employ sensors to identify the temperature outdoors and indoors. If a sensor malfunctions, you might see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can swap out the sensor and reboot the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear if the thermostat is unable to detect a heating or cooling unit. This might mean that the equipment itself is faulty and unable to communicate with the thermostat. This sometimes happens when the wiring is bad or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can employ a voltmeter to determine if there’s a poor electrical connection. When 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 notice error code e2 appear on your Honeywell smart thermostat, it might mean several different things. For example, one of the sensors responsible for detecting the temperature isn’t working correctly. In other cases, it means the router was disconnected from power before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is a result of sensor failure, a technician will troubleshoot and switch out the damaged sensor. If the problem comes from disconnected power, all you’ll have to do is see to it that the router remains on throughout the setup process.