A Honeywell smart thermostat is an excellent way to optimize how you use your heating and cooling. But like any mechanical system, you might sometimes run into a problem. With a digital display, Honeywell smart thermostats can provide an error code that certified technicians can use to get a better sense of what's wrong. Here are some of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You may encounter this error code when your home’s Wi-Fi internet did not present an IP address for the thermostat to connect to. This can occur if the router doesn't execute the Dynamic Host Configuration Protocol, or DHCP. This function automatically sends out the necessary IP address for your thermostat to connect to the Wi-Fi.
How to Fix Honeywell Thermostat Error e42
You can resolve error code e42 by making sure that your router has enabled DHCP. Assuming it does, you usually also need to power cycle the router and perform the setup process again with the thermostat. Completing this task should ensure the DHCP is transmitted and connects to your smart thermostat.
Honeywell Thermostat Error e02
Error code e02 is displayed when the password for connecting to your home’s Wi-Fi router is incorrect. After this error code has appeared for 30 seconds, the thermostat’s digital display will automatically progress to the Wi-Fi setup screen so you can try the password again.
How to Fix Honeywell Thermostat Error e02
All you need to do to resolve error e02 is verify you’re typing the correct Wi-Fi password when configuring the thermostat.
Honeywell Thermostat Error 40
Error code 40 can pop up when the thermostat is informed that a heat pump or air conditioner’s monitoring system has detected a malfunction. For the most part, this occurs if the compressor isn’t turning on despite being instructed to. But this error code can also show up if power is disconnected from the outdoor unit for a long period of time. A “High Pressure Fault” error, induced by obstructed airflow, can render this error code. Finally, you might encounter error code 40 if there’s something wrong with the coolant, the outdoor unit’s fan motor or the motor’s starting capacitor.
How to Fix Honeywell Thermostat Error 40
You can examine the air filter for signs of a clog, as well as the breakers and indoor unit’s blower for ordinary operation. If you reset the thermostat and error code 40 reappears, it's time to get a hold of an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat presents error code e43, it can’t communicate with the router, and by extension the Wi-Fi. This can 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
Restart the router by unplugging it and leaving it that way for around 30 seconds. The thermostat might also be disconnected if you’ve recently changed the password or the Wi-Fi’s SSID, which is the name you give it.
Honeywell Thermostat Error e1
Thermostats use sensors to determine the temperature outdoors and indoors. If a sensor breaks down, you could see error code e1 show up on your Honeywell smart thermostat.
How to Fix Honeywell Thermostat Error e1
A trained technician can replace the sensor and restart the thermostat, which should take care of error code e1.
Honeywell Thermostat Error 11n
Error code 11n can appear when the thermostat can’t detect a heating or cooling unit. This can mean that the equipment itself is malfunctioning and unable to maintain a connection to 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 licensed technician can employ a voltmeter to assess if there’s a poor electrical connection. In situations where the wiring on your specific HVAC equipment is bad, the technician can replace it. In situations where the thermostat itself is the source of the error code, it should probably be replaced.
Honeywell Thermostat Error e2
If you see error code e2 show up on your Honeywell smart thermostat, it might mean a couple of different things. For example, one of the sensors used to detect the temperature isn’t operating correctly. In other instances, it means the router was disconnected from power before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
When the error code stems from sensor failure, a technician will troubleshoot and switch out the impacted sensor. When 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.