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 run into a problem. With a digital display, Honeywell smart thermostats can provide an error code that trained technicians can use to understand what's going on. Here are some of the most likely error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might see this error code when your home’s Wi-Fi connection did not present an IP address for the thermostat to connect with. This can occur if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the necessary 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 can complete the DHCP. If it does, you may also need to power cycle the router and complete the initial setup process again with the thermostat. This should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed whenever the password for communicating with your home’s Wi-Fi router was incorrect. After this error code has appeared for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to clear error e02 is verify you’re typing 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. Most often, this appears when the compressor isn’t running despite being directed to. But this error code may 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 display this error code. And finally, you could encounter error code 40 if there’s something wrong 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 ordinary operation. If you turn the thermostat off and on again and error code 40 reappears, it's time 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 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 around 30 seconds. The thermostat may also be disconnected if you have recently updated 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 malfunctions, you might see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can change out the sensor and reset the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear when the thermostat is unable to recognize a heating or cooling unit. This may mean that the equipment itself is malfunctioning and unable to communicate 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 professional technician can utilize a voltmeter to find out if there’s a faulty electrical connection. When the wiring on your existing HVAC system is bad, the technician can replace it. If the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 appear on your Honeywell smart thermostat, it can mean a couple of different things. Sometimes, one of the sensors that detects the temperature isn’t operating like it should. 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 can troubleshoot and switch out the damaged sensor. When the problem comes from disconnected power, all you’ll have to do is make sure the router stays on throughout the setup process.