A Honeywell smart thermostat is an easy way to optimize how you use your heating and cooling. But like any technology, you might sometimes run into a problem. With a digital display, Honeywell smart thermostats can provide an error code that certified technicians use to understand what's wrong. Here are several of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Error Code e42
You may see this error code if 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 doesn't execute the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically transmits the needed IP address for your thermostat to connect to the Wi-Fi.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by making sure that your router is enabled for DHCP. When it does, you usually also have to power cycle the router and repeat the initial setup process with the thermostat. This should see to it that the DHCP is transmitted and connects to your smart thermostat.
Honeywell Error Code e02
Error code e02 appears if the password for accessing your home’s Wi-Fi router is not correct. 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 need to do to resolve error e02 is make sure 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 notified that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most often, this occurs when the compressor isn’t running despite being instructed to. But this error code could also surface if power is shut off from the outdoor unit for a long period of time. A “High Pressure Fault” error, caused by poor airflow, can display this error code. Finally, you could encounter error code 40 if there’s an issue with the refrigerant, 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 restart the thermostat and error code 40 reappears, you should try to get a hold of an experienced technician.
Honeywell Error Code e43
If the Honeywell thermostat shows error code e43, it can’t communicate with the router, and by extension the Wi-Fi. This may 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 around 30 seconds. The thermostat may also be disconnected if you have recently switched the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to determine the temperature outdoors and indoors. If a sensor breaks down, 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 reset the thermostat, which should take care of error code e1.
Honeywell Error Code 11n
Error code 11n can appear in situations where the thermostat is unable to recognize a heating or cooling unit. This can mean that the equipment itself is malfunctioning and unable to connect with 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 qualified technician can employ a voltmeter to assess if there’s a bad electrical connection. When the wiring on your specific HVAC equipment 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. For example, one of the sensors responsible for detecting the temperature isn’t working like it should. 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
When the error code is caused by sensor failure, a technician will troubleshoot and swap out the impacted sensor. Any time the problem stems from disconnected power, all you'll need to do is see to it that the router remains on throughout the setup process.