A Honeywell smart thermostat is an easy way to better manage how you use your heating and cooling. But like any utility, you may sometimes experience a problem. With its digital display, Honeywell smart thermostats can show an error code that trained technicians will use to understand what's happening. Here are several of the most common error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may receive this error code when your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect to. This can occur if a router doesn't execute the Dynamic Host Configuration Protocol, or DHCP. This process automatically sends out the necessary 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 is enabled for DHCP. When it does, you might also have to power cycle the router and complete the initial setup process again with your thermostat. This should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears whenever the password for communicating with your home’s Wi-Fi router was 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 try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to resolve error e02 is verify you’re typing the correct Wi-Fi password when setting up 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 recognized a malfunction. Most commonly, this happens when the compressor isn’t working despite being directed to. But this error code can also appear if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by obstructed airflow, can render this error code. And finally, you could encounter error code 40 if there’s an issue with the coolant, 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 regular 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 the Honeywell thermostat shows error code e43, it can’t communicate with the router, and by extension your 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
Reset the router by unplugging it and leaving it that way for about 30 seconds. The thermostat may also be disconnected if you’ve recently switched the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats employ sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you might notice error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can change out the sensor and restart the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear if the thermostat can’t detect a heating or cooling unit. This can mean that the equipment itself is faulty and unable to maintain a connection to the thermostat. This can happen when the wiring is damaged or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to find out if there’s a faulty electrical connection. In situations where the wiring on your type of 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 pop 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 operating like it should. Other times, it means the router was disconnected from its power source 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 will troubleshoot and switch out the impacted sensor. Any time the problem comes from disconnected power, all you have to do is see to it that the router remains on during the setup process.