A Honeywell smart thermostat is an easy way to better manage how you use your home comfort system. But like any mechanical system, you might occasionally experience a problem. With a digital display, Honeywell smart thermostats can provide an error code that trained technicians can use to understand what's happening. Here are some of the most common error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may encounter this error code when your home’s Wi-Fi connection did not provide an IP address for the thermostat to connect to. This can occur if the router fails to complete the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the needed IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by making sure that your router has enabled DHCP. If it does, you may also need to power cycle the router and complete the initial setup process again with your thermostat. Completing this task should see to it that the DHCP is delivered and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed when the password for connecting to your home’s Wi-Fi router is not correct. Once 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 try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to solve error e02 is make sure 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 notified that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this appears once the compressor isn’t running despite being directed to. But this error code can also show up if power is disconnected from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, triggered by obstructed airflow, can render this error code. And finally, you might encounter 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 examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for ordinary operation. If you reset the thermostat and error code 40 reappears, it's time to contact an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents 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 the wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reset the router by unplugging it and leaving it that way for around 30 seconds. The thermostat could also be disconnected if you’ve 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 determine 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 qualified technician can swap out the sensor and restart the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear in situations where the thermostat can’t recognize a heating or cooling unit. This might mean that the equipment itself is defective and unable to connect with the thermostat. This can happen 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 find out if there’s a bad electrical connection. If the wiring on your existing HVAC equipment is bad, the technician can replace it. When 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 a few different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t working correctly. In other instances, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code stems from sensor failure, a technician should troubleshoot and switch out the damaged sensor. Any time the problem comes from disconnected power, all you'll need to do is make sure the router remains on throughout the setup process.