Honeywell thermostat error codes

Honeywell RTH6500WF Wi-Fi Series thermostat error codes

Error Code	Cause	Action
E01	During Wi-Fi Setup, the router lost power	• Ensure your router has power.
		• If trying to connect to a hidden or manually added network, confirm the router has power and is working.
E02	Invalid Wi-Fi password. This code displays for 30 seconds, then the thermostat will re-enter Wi-Fi Setup mode	• Re-enter password for your home Wi-Fi network.
		• Repeat setup process and confirm your password for your home Wi-Fi network
E42	Router is not issuing an IP address to the thermostat.	• Wait for 30 minutes, connection can take several minutes.
		• If still no connection, remove thermostat from wallplate for 10 seconds, then reconnect it
		• Verify your router is correctly setup to automatically give IP addresses.
E43	No internet connection. Thermostat cannot communicate to Total Connect Comfort.	• Make sure the Internet cable is plugged in.
		• Reboot the router.
E99	General error	Remove thermostat from wallplate for 10 seconds, then reconnect it

Problem	Solution
Cooling system does not turn on.	• Set the system to Cool by pressing the System button.
	• Check the cool temperature setting to be sure it is set below room temperature and “Cool On" shows solidly in the display.
	• Check the circuit breaker to be sure it is not tripped.
	• Check the power switch at the heating and/or cooling system to be sure it is on.
	• Check the furnace door to be sure it is closed securely.
	• Wait five minutes for the cooling system to respond.
	• If all of this was checked, contact your local heating and cooling contractor.
“Heat On" is not shown in the display.	Set System setting to Heat and set the temperature setting above the room temperature. If “Heat On” is shown solidly in the display, but the heating system does not turn on.
“Cool On” is not shown in the display.	Set System setting to Cool and set the temperature setting below the room temperature. If “Cool On” is shown solidly in the display, but the cooling system does not turn on.
“Heat On” is flashing in the display (heat pumps only).	Compressor minimum-off timer is active. Wait up to five minutes for the heating system to turn on.
“Cool On” is flashing in the display.	Compressor minimum-off timer is active. Wait up to five minutes for the cooling system to turn on.