A Honeywell smart thermostat is a great way to fine-tune how you use your home comfort system. But like any technology, you may occasionally experience a problem. With its digital display, Honeywell smart thermostats can show an error code that trained technicians can use to understand what's going on. Here are several of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may encounter this error code in the event that your home’s Wi-Fi internet did not present an IP address for the thermostat to connect to. This can take place if the router does not perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically transmits the needed IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by confirming that your router is enabled for DHCP. If it does, you might also need to power cycle the router and repeat the initial setup process with your thermostat. Doing so should ensure the DHCP is delivered and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs when the password for accessing your home’s Wi-Fi router is not correct. Once this error code appears for 30 seconds, the thermostat’s digital display will automatically progress 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 solve error e02 is make sure you’re entering 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 recognized a malfunction. Most commonly, this appears if the compressor isn’t running despite being directed to. But this error code can also appear if power is disconnected from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by blocked airflow, can display this error code. Finally, you could see 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 inspect the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for ordinary operation. If you restart the thermostat and error code 40 reappears, you should try to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat shows error code e43, it can’t communicate with the router, and by extension the Wi-Fi. This might 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
Restart the router by unplugging it and leaving it that way for about 30 seconds. The thermostat could also be disconnected if you have recently changed the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to identify the temperature outdoors and indoors. If a sensor malfunctions, you could see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A skilled technician can replace the sensor and reset the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear in situations where the thermostat is failing to detect a heating or cooling unit. This might mean that the equipment itself is faulty and unable to maintain a connection to the thermostat. This can happen when the wiring is defective or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can employ a voltmeter to determine if there’s a bad electrical connection. If the wiring on your specific HVAC system 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 see error code e2 pop up on your Honeywell smart thermostat, it could mean several different things. Sometimes, one of the sensors used to detect the temperature isn’t operating correctly. In other instances, it means the router was disconnected from its power source before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code stems from sensor failure, a technician will troubleshoot and replace the damaged sensor. When the problem originates from disconnected power, all you'll need to do is make sure the router stays on during the setup process.