If you no longer need to use a Wi-Fi (wireless LAN) connection with your printer, you can disable it.
By removing unnecessary Wi-Fi signals, you can also reduce the load on your standby power.
Turn off the printer if it is on.
Turn the printer on while holding down the 
button.
The default network settings are restored and the Wi-Fi connection is disabled.
You need to reconfigure network settings to use Wi-Fi again.