A Honeywell smart thermostat is a great way to fine-tune 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 professional technicians will use to understand what's wrong. Here are some of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can encounter this error code when your home’s Wi-Fi connection did not provide an IP address for the thermostat to connect with. This can occur if a router fails to execute the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits the necessary IP address for your thermostat to connect to the Wi-Fi.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by confirming that your router can complete the DHCP. When it does, you usually also need to power cycle the router and perform the setup process again with the thermostat. Doing so should see to it that the DHCP is delivered and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed whenever the password for connecting to your home’s Wi-Fi router is not correct. When this error code has appeared for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is ensure you’re putting in the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 40
Error code 40 can pop up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most often, this happens if the compressor isn’t working despite being directed to. But this error code could also surface if power is disconnected from the outdoor unit for a long period of time. A “High Pressure Fault” error, triggered by poor airflow, can lead to this error code. And finally, you could encounter 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 inspect the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you turn the thermostat off and on again and error code 40 reappears, it’s best to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat displays 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 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 may also be disconnected if you have recently switched the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats employ sensors to detect the temperature outdoors and indoors. If a sensor breaks down, you could see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and restart the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where 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 is faulty.
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 existing HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the issue, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 appear on your Honeywell smart thermostat, it could mean a few different things. For example, one of the sensors that detects the temperature isn’t functioning properly. In other cases, 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 is a result of sensor failure, a technician will troubleshoot and replace the damaged sensor. If the problem comes from disconnected power, all you have to do is verify the router stays on throughout the setup process.