A Honeywell smart thermostat is a great way to fine-tune how you use your home comfort system. But like any utility, you could sometimes run into a problem. With its digital display, Honeywell smart thermostats can display an error code that trained technicians use to understand what's happening. Here are some of the most known error codes you might see on your Honeywell smart thermostat.
Honeywell Thermostat Error e42
You might see this error code in the event that your home’s Wi-Fi connection did not supply an IP address for the thermostat to connect to. This can occur if your router does not perform 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 clear error code e42 by verifying that your router has enabled DHCP. If it does, you might also need to power cycle the router and perform the setup process again with your thermostat. Completing this task should see to it that the DHCP is transmitted and connects to the smart thermostat.
Honeywell Thermostat Error e02
Error code e02 appears whenever the password for connecting to your home’s Wi-Fi router is not correct. When this error code is displayed 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 clear error e02 is make sure you’re putting in the correct Wi-Fi password when setting up the thermostat.
Honeywell Thermostat Error 40
Error code 40 can pop up when the thermostat is notified that a heat pump or air conditioner’s monitoring system has recognized a malfunction. Most commonly, this happens once the compressor isn’t turning on despite being directed to. But this error code can also show up if power is shut off from the outdoor unit for an extended period of time. A “High Pressure Fault” error, triggered by poor airflow, can lead to this error code. Finally, you could experience error code 40 if there’s an issue with the refrigerant, 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 restart the thermostat and error code 40 reappears, you should try to get in touch with an experienced technician.
Honeywell Thermostat Error e43
If a Honeywell thermostat displays error code e43, it is failing 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
Restart the router by unplugging it and leaving it that way for a short period. The thermostat could also be disconnected if you have recently changed 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 fails, you may 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 restart 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 malfunctioning and unable to connect with 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 qualified technician can utilize a voltmeter to determine if there’s a poor electrical connection. In situations where the wiring on your existing HVAC equipment is bad, the technician can replace it. When the thermostat itself is the problem, it will likely have to be replaced.
Honeywell Thermostat Error e2
If you notice error code e2 pop up 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. Other times, it means the router was disconnected from power before the thermostat finished the setup process.
How to Fix Honeywell Thermostat Error e2
If the error code stems from sensor failure, a technician will troubleshoot and swap out the impacted sensor. When the problem stems from disconnected power, all you'll need to do is make sure the router stays on during the setup process.