A Honeywell smart thermostat is an excellent way to fine-tune how you use your HVAC system. But like any technology, you may sometimes run across a problem. With the digital display, Honeywell smart thermostats can provide an error code that professional technicians can use to understand what's happening. Here are a few of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Error Code e42
You might receive this error code if your home’s Wi-Fi internet did not provide an IP address for the thermostat to connect to. This can occur if a router doesn't perform the Dynamic Host Configuration Protocol, or DHCP. This function 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 verifying that your router is enabled for DHCP. Assuming it does, you usually also need to power cycle the router and complete the initial setup process again with your thermostat. This should see to it that the DHCP is sent and connects to your smart thermostat.
Error Code e02 for Honeywell Thermostats
Error code e02 is displayed if the password for communicating with your home’s Wi-Fi router is not correct. After this error code appears for 30 seconds, the thermostat’s digital display will automatically progress 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 solve error e02 is ensure you’re putting in the correct Wi-Fi password when configuring the thermostat.
Error Code 40 for Honeywell Thermostats
Error code 40 can appear when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has detected a malfunction. Most often, this appears when the compressor isn’t working despite being directed to. But this error code can also surface if power is shut off from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, caused by blocked airflow, can render this error code. Finally, you may encounter 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 check the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for normal operation. If you turn the thermostat off and on again and error code 40 reappears, it’s best to get in touch with an experienced technician.
Honeywell Error Code e43
If your Honeywell thermostat presents error code e43, it is unable to 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 the 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 changed the password or the Wi-Fi’s SSID, which is the name you give it.
Error Code e1 for Honeywell Thermostats
Thermostats employ sensors to identify the temperature outdoors and indoors. If a sensor fails, you might see 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 resolve error code e1.
Honeywell Error Code 11n
Error code 11n may appear in situations where the thermostat is failing to connect to a heating or cooling unit. This may mean that the equipment itself is malfunctioning and unable to communicate with the thermostat. This sometimes happens when the wiring is damaged or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can use 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. When the thermostat itself is the problem, it should probably be replaced.
Honeywell Error Code e2
If you’ve noticed error code e2 pop up on your Honeywell smart thermostat, it could mean a few different things. For example, one of the sensors used to detect the temperature isn’t operating like it should. In other instances, it means the router was disconnected from the outlet before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
In situations where the error code is a result of sensor failure, a technician should troubleshoot and switch out the impacted sensor. If the problem stems from disconnected power, all you’ll have to do is make sure the router stays on over the course of the setup process.