A Honeywell smart thermostat is an easy way to optimize how you use your home comfort system. But like any technology, you could sometimes run into a problem. With the digital display, Honeywell smart thermostats can show an error code that certified technicians will use to get a better sense of what's going on. Here are a few of the most likely 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 internet did not provide an IP address for the thermostat to connect to. This can occur if a router does not perform 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 clear error code e42 by making sure that your router is enabled for DHCP. If it does, you usually also need to power cycle the router and complete the initial setup process again with the thermostat. Completing this task should ensure the DHCP is transmitted and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears when the password for accessing your home’s Wi-Fi router is incorrect. When this error code is displayed 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 solve 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 show up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has detected a malfunction. For the most part, this occurs when the compressor isn’t turning on despite being directed to. But this error code may also show up if power is disconnected from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, triggered by poor airflow, can render this error code. Finally, you could 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 restart the thermostat and error code 40 reappears, it's time to contact an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat shows error code e43, it can’t 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 your wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reboot the router by unplugging it and leaving it that way for around 30 seconds. The thermostat could also be disconnected if you’ve 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 determine the temperature outdoors and indoors. If a sensor breaks down, you may see error code e1 show up 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 could appear when the thermostat is unable to detect a heating or cooling unit. This can mean that the equipment itself is malfunctioning 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 professional technician can utilize a voltmeter to determine if there’s a poor electrical connection. When the wiring on your type of HVAC equipment is bad, the technician can replace it. When the thermostat itself is the problem, it should probably be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 show up on your Honeywell smart thermostat, it might mean several different things. For example, one of the sensors responsible for detecting the temperature isn’t functioning correctly. In other instances, it means the router was disconnected from the outlet before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is a result of sensor failure, a technician should troubleshoot and swap out the damaged sensor. When the problem originates from disconnected power, all you’ll have to do is verify the router stays on during the setup process.