A Honeywell smart thermostat is an excellent way to better manage how you use your HVAC system. But like any utility, you might sometimes run into a problem. With its digital display, Honeywell smart thermostats can display an error code that certified technicians use to get a better sense of what's happening. Here are some of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Error Code e42
You can encounter this error code if your home’s Wi-Fi internet did not present an IP address for the thermostat to hook up to. This can happen if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This procedure automatically supplies the required IP address for your thermostat to connect.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by making sure that your router can complete the DHCP. If it does, you might also have to power cycle the router and perform the setup process again with your thermostat. Completing this task should see to it that the DHCP is sent and connects to the smart thermostat.
Honeywell Error Code e02
Error code e02 occurs whenever the password for communicating with your home’s Wi-Fi router is not correct. After 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 attempt to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you'll need to do to clear error e02 is verify you’re typing the correct Wi-Fi password when configuring 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 identified a malfunction. Most often, this occurs if the compressor isn’t running despite being directed to. But this error code may also appear if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, triggered by obstructed airflow, can render this error code. Finally, you could experience error code 40 if there’s something wrong 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 normal operation. If you restart the thermostat and error code 40 reappears, it's time to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If your Honeywell thermostat displays error code e43, it is failing to communicate with the router, and by extension your Wi-Fi. This can 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
Reset the router by unplugging it and leaving it that way for a short period. 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 Error Code e1
Thermostats employ sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you might 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 reset the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear when the thermostat is unable to detect a heating or cooling unit. This can 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 has failed.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to assess if there’s a bad electrical connection. If the wiring on your existing HVAC equipment is bad, the technician can replace it. When the thermostat itself is the problem, it should probably be replaced.
Error Code e2 for Honeywell Thermostats
If you notice error code e2 show up on your Honeywell smart thermostat, it can mean several different things. For example, one of the sensors that detects the temperature isn’t operating properly. In other instances, it means the router was disconnected from power before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is a result of sensor failure, a technician will troubleshoot and replace the impacted sensor. If the problem originates from disconnected power, all you have to do is see to it that the router stays on throughout the setup process.