A Honeywell smart thermostat is an excellent way to fine-tune how you use your home comfort system. But like any technology, you may sometimes run across a problem. With its digital display, Honeywell smart thermostats can display an error code that trained technicians will use to figure out what's wrong. Here are some of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Error Code e42
You may receive this error code when your home’s Wi-Fi internet did not present an IP address for the thermostat to connect with. This can occur if the router fails to execute the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits the necessary 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 might also need to power cycle the router and perform the setup process again with the thermostat. Doing so should ensure the DHCP is delivered and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 occurs if the password for accessing your home’s Wi-Fi router is not correct. Once this error code has appeared for 30 seconds, the thermostat’s digital display should automatically transition to the Wi-Fi setup screen so you can attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to clear error e02 is make sure you’re typing the correct Wi-Fi password when configuring the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can show up when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most often, this happens once the compressor isn’t turning on despite being instructed to. But this error code could also surface if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, triggered by blocked airflow, can lead to this error code. And finally, you could see error code 40 if there’s a problem with the refrigerant, 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 regular operation. If you restart the thermostat and error code 40 reappears, it's time to contact an experienced technician.
Error Code e43 for Honeywell Thermostats
If the Honeywell thermostat displays error code e43, it can’t communicate with the router, and by extension your 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
Reset the router by unplugging it and leaving it that way for a short period. The thermostat might also be disconnected if you recently switched the password or the Wi-Fi’s SSID, which is the name you provide it.
Honeywell Thermostat Error e1
Thermostats use sensors to detect the temperature outdoors and indoors. If a sensor breaks down, you could notice error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can swap out the sensor and restart the thermostat, which should resolve error code e1.
Honeywell Error Code 11n
Error code 11n can appear if the thermostat is failing to recognize a heating or cooling unit. This may mean that the equipment itself is faulty and unable to connect with the thermostat. This can happen when the wiring is bad 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 poor electrical connection. When 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 should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 show up on your Honeywell smart thermostat, it might mean a few different things. Sometimes, one of the sensors that detects the temperature isn’t operating properly. In other cases, it means the router was disconnected from its power source before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code is caused by sensor failure, a technician should troubleshoot and switch out the damaged sensor. Any time the problem stems from disconnected power, all you have to do is make sure the router stays on throughout the setup process.
