A Honeywell smart thermostat is an easy way to fine-tune how you use your heating and cooling. But like any technology, you might occasionally run across a problem. With the digital display, Honeywell smart thermostats can show an error code that trained technicians use to get a better sense of what's happening. 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 when your home’s Wi-Fi internet did not present an IP address for the thermostat to hook up to. This can take place if the router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically transmits the needed IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can fix error code e42 by making sure that your router has enabled DHCP. When it does, you usually also need to power cycle the router and perform the setup process again with the thermostat. This should see to it that the DHCP is transmitted and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs if the password for accessing your home’s Wi-Fi router is not correct. Once this error code is displayed for 30 seconds, the thermostat’s digital display should automatically transition 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 entering 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 recognized a malfunction. Most often, this occurs once the compressor isn’t running despite being directed to. But this error code can also show up if power is shut off from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by blocked airflow, can display this error code. Lastly, you might encounter error code 40 if there’s a problem 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 regular operation. If you reset the thermostat and error code 40 reappears, you should try to contact an experienced technician.
Honeywell Thermostat Error e43
If the Honeywell thermostat presents error code e43, it can’t communicate with the router, and by extension the Wi-Fi. This could 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 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 utilize sensors to identify the temperature outdoors and indoors. If a sensor fails, you might see error code e1 turn up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can swap out the sensor and reset the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear when the thermostat can’t connect to a heating or cooling unit. This may mean that the equipment itself is faulty and unable to connect with the thermostat. This sometimes happens when the wiring is damaged or even if the thermostat has failed.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to determine if there’s a bad electrical connection. In situations where the wiring on your type of HVAC equipment is bad, the technician can replace it. If 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 might mean a couple of different things. In some cases, one of the sensors that detects the temperature isn’t functioning properly. In other cases, it means the router was disconnected from power before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code is caused by sensor failure, a technician will troubleshoot and swap out the damaged sensor. When the problem comes from disconnected power, all you have to do is make sure the router remains on over the course of the setup process.