A Honeywell smart thermostat is a great way to optimize how you use your HVAC system. But like any utility, you could sometimes run into a problem. With the digital display, Honeywell smart thermostats can show an error code that trained technicians will use to get a better sense of what's happening. Here are a few of the most likely error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may receive this error code in the event that your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect with. This can occur if the router does not perform the Dynamic Host Configuration Protocol, or DHCP. This process automatically sends out 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 confirming that your router is enabled for DHCP. If it does, you may also need to power cycle the router and repeat the initial setup process with the thermostat. Doing so should see to it that the DHCP is sent and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs when the password for connecting to your home’s Wi-Fi router was incorrect. Once this error code is displayed for 30 seconds, the thermostat’s digital display automatically transitions to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you have to do to solve 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 notified that a heat pump or air conditioner’s monitoring system has recognized a malfunction. For the most part, this happens if the compressor isn’t running despite being instructed to. But this error code could also show up if power is disconnected from the outdoor unit for a lengthy period of time. A “High Pressure Fault” error, triggered by poor airflow, can lead to this error code. Lastly, you might encounter 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 turn the thermostat off and on again and error code 40 reappears, it's time to contact an experienced technician.
Honeywell Thermostat Error e43
If your Honeywell thermostat displays 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 your wide area network (WAN).
How to Fix Honeywell Thermostat Error e43
Reset the router by unplugging it and leaving it that way for around 30 seconds. The thermostat might also be disconnected if you have recently updated the password or the Wi-Fi’s SSID, which is the name you create for it.
Honeywell Thermostat Error e1
Thermostats use sensors to identify the temperature outdoors and indoors. If a sensor breaks down, you might see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A qualified technician can change out the sensor and reset the thermostat, which should resolve error code e1.
Honeywell Thermostat Error 11n
Error code 11n may appear if 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 bad or even if the thermostat is faulty.
How to Fix Honeywell Thermostat Error 11n
A qualified technician can utilize a voltmeter to assess if there’s a poor electrical connection. In situations where the wiring on your type of HVAC system is bad, the technician can replace it. If the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you’ve noticed error code e2 pop up on your Honeywell smart thermostat, it could mean several different things. Sometimes, one of the sensors responsible for detecting the temperature isn’t functioning correctly. In other instances, it means the router was disconnected from the outlet before the thermostat could complete the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code stems from sensor failure, a technician should troubleshoot and swap out the affected sensor. When the problem originates from disconnected power, all you have to do is make sure the router remains on during the setup process.