A Honeywell smart thermostat is an easy way to fine-tune how you use your home comfort system. But like any mechanical system, you might sometimes run across a problem. With the digital display, Honeywell smart thermostats can display an error code that trained technicians will use to understand what's wrong. Here are a few of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may encounter this error code if your home’s Wi-Fi connection did not provide an IP address for the thermostat to hook up to. This can take place if the router does not execute the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the required 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 has enabled DHCP. When it does, you might also have 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 Error Code e02
Error code e02 appears whenever the password for communicating with your home’s Wi-Fi router is incorrect. After this error code appears for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to resolve 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 informed that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this appears when the compressor isn’t running despite being directed to. But this error code could also show up if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, induced by blocked airflow, can lead to this error code. Lastly, you might see 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 examine 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, you should try to get a hold of an experienced technician.
Honeywell Error Code e43
If the Honeywell thermostat displays error code e43, it is failing to communicate with the router, and by extension the Wi-Fi. This could 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
Restart the router by unplugging it and leaving it that way for about 30 seconds. The thermostat could also be disconnected if you recently changed the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you may see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can replace the sensor and reboot the thermostat, which should clear error code e1.
Error Code 11n for Honeywell Thermostats
Error code 11n can appear in situations where the thermostat is failing to detect a heating or cooling unit. This can mean that the equipment itself is defective 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 qualified technician can employ a voltmeter to find out if there’s a poor electrical connection. When the wiring on your type of HVAC equipment is bad, the technician can replace it. If the thermostat itself is the source of the error code, it should probably be replaced.
Error Code e2 for Honeywell Thermostats
If you notice error code e2 show up on your Honeywell smart thermostat, it could mean several different things. For example, one of the sensors responsible for detecting the temperature isn’t operating like it should. In other cases, it means the router was disconnected from its power source before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code stems from sensor failure, a technician will troubleshoot and switch out the damaged sensor. When the problem originates from disconnected power, all you’ll have to do is make sure the router remains on throughout the setup process.