Hi Virgo,
It starts after you open the water valve, and the ice is formed; however, it is recommended that you run water through the dispenser for about 7 minutes. This is to remove impurities and air from the water line.
Should you need further assistance with the refrigerator, please feel free to get back to us via the following options:
1. Facebook Messenger: http://m.me/Samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.community.Samsung.com/t5/Samsung-Community/ct-p/us
Please provide us with this reference number (1149283075) to help our team pull up your information when you message us.
Have a great day,
-Ernest-
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