A Honeywell smart thermostat is an excellent way to better manage how you use your home comfort system. But like any mechanical system, you could sometimes experience a problem. With the digital display, Honeywell smart thermostats can display an error code that professional technicians can use to understand what's happening. Here are some of the most known error codes you could see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You can encounter this error code if your home’s Wi-Fi internet did not supply an IP address for the thermostat to connect with. This can occur if your router fails to perform the Dynamic Host Configuration Protocol, or DHCP. This function automatically transmits the necessary IP address for your thermostat to link up.
How to Fix Honeywell Thermostat Error e42
You can clear error code e42 by confirming that your router has enabled DHCP. Assuming it does, you usually also have to power cycle the router and repeat the initial setup process with the thermostat. Doing so should ensure the DHCP is transmitted and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 occurs when the password for communicating with your home’s Wi-Fi router is incorrect. When 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'll need to do to solve 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 alerted that a heat pump or air conditioner’s monitoring system has identified a malfunction. Most commonly, this happens when the compressor isn’t working despite being instructed to. But this error code can 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. 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 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 best to get a hold of 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 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 provide it.
Honeywell Thermostat Error e1
Thermostats utilize sensors to detect the temperature outdoors and indoors. If a sensor malfunctions, you might see error code e1 appear on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can swap out the sensor and reboot the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n could appear if the thermostat is unable to detect a heating or cooling unit. This might 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 is faulty.
How to Fix Honeywell Thermostat Error 11n
A professional technician can use a voltmeter to find out if there’s a bad electrical connection. In situations where the wiring on your existing HVAC system is bad, the technician can replace it. In situations where the thermostat itself is the issue, it should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 appear on your Honeywell smart thermostat, it might mean a few different things. Sometimes, one of the sensors that detects the temperature isn’t working like it should. In other instances, it means the router was disconnected from power before the thermostat completed the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code is caused by sensor failure, a technician can troubleshoot and swap out the impacted sensor. Any time the problem comes from disconnected power, all you’ll have to do is verify the router stays on during the setup process.