A Honeywell smart thermostat is an easy way to optimize how you use your heating and cooling. But like any utility, you could occasionally run into a problem. With the digital display, Honeywell smart thermostats can display an error code that certified technicians will use to get a better sense of what's wrong. Here are several of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may see this error code if your home’s Wi-Fi connection did not present an IP address for the thermostat to connect with. This can take place if your router does not perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically supplies the needed IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by verifying that your router is enabled for DHCP. When it does, you usually also need to power cycle the router and perform the setup process again with your thermostat. Completing this task should ensure the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs whenever the password for accessing your home’s Wi-Fi router was incorrect. Once this error code appears 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'll need to do to resolve error e02 is ensure you’re typing 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 detected a malfunction. Most commonly, this occurs once the compressor isn’t turning on despite being instructed to. But this error code can also surface if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, induced by poor airflow, can lead to this error code. Finally, you could experience 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 examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you restart the thermostat and error code 40 reappears, it’s best to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents error code e43, it is failing to communicate with the router, and by extension your Wi-Fi. This may 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 about 30 seconds. The thermostat could also be disconnected if you 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 could see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified 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 can appear when the thermostat can’t detect 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 damaged or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can employ a voltmeter to determine if there’s a faulty electrical connection. If the wiring on your type of HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the issue, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 show up on your Honeywell smart thermostat, it could mean several different things. In some cases, one of the sensors that detects the temperature isn’t operating 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
If the error code is a result of sensor failure, a technician should troubleshoot and swap out the damaged sensor. Any time the problem comes from disconnected power, all you have to do is verify the router remains on during the setup process.