A Honeywell smart thermostat is an excellent way to fine-tune how you use your home comfort system. But like any technology, you could occasionally experience a problem. With its digital display, Honeywell smart thermostats can provide an error code that professional technicians can use to figure out what's going on. Here are several of the most known error codes you may see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may see this error code in the event that your home’s Wi-Fi internet did not present an IP address for the thermostat to connect with. This can happen if your router does not complete the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits the necessary 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 has enabled DHCP. If it does, you usually also need to power cycle the router and perform the setup process again with your 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 communicating with your home’s Wi-Fi router is not correct. When this error code appears for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can try to enter the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to clear error e02 is verify you’re putting in the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 40
Error code 40 can appear when the thermostat is alerted that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this happens when the compressor isn’t turning on despite being instructed to. But this error code could also surface if power is disconnected from the outdoor unit for an extended period of time. A “High Pressure Fault” error, caused by obstructed airflow, can render this error code. And 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 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 best to get in touch with an experienced technician.
Error Code e43 for Honeywell Thermostats
If the Honeywell thermostat displays error code e43, it is unable to 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 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 have recently updated the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Error Code e1
Thermostats employ sensors to detect the temperature outdoors and indoors. If a sensor fails, you might notice error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can change out the sensor and reset the thermostat, which should clear error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear in situations where the thermostat can’t recognize a heating or cooling unit. This might mean that the equipment itself is malfunctioning and unable to communicate 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 licensed technician can utilize a voltmeter to determine if there’s a bad electrical connection. When the wiring on your type of HVAC system is bad, the technician can replace it. When the thermostat itself is the source of the error code, it will likely have to be replaced.
Error Code e2 for Honeywell Thermostats
If you notice error code e2 pop up on your Honeywell smart thermostat, it might mean several different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t functioning like it should. 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
In situations where the error code stems from sensor failure, a technician should troubleshoot and replace the impacted sensor. If the problem comes from disconnected power, all you'll need to do is see to it that the router stays on throughout the setup process.