Hello yosemite,
Thank you for reaching out and letting us know your inquiry about the AddWash feature of this Samsung washer. We understand that this information may be essential for you to know. We're here to help.
As per checking, the AddWash feature is if you have forgotten some clothes or want to add a special softener, the add wash alarm reminds you to add any laundry or softener after your wash has already started. When the Add Wash indicator turns on, you can stop the washer and put additional laundry into the drum. The Add Door opens by more than 100° for easy access.
For reference, see pages 44-47 of the user manual to know more about operating this Samsung washer.
https://downloadcenter.samsung.com/content/UM/201904/20190416094610364/USER_WF45K6500AV_DC68-03665A-03_A2.pdf
For other concerns, do not hesitate to reach out via our Support Channels below:
1. Facebook Messenger: http://m.me/samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.commuity.samsung.com/t5/Samsung-Community/ct-p/us
Thank you, and stay safe!
Your Reference Ticket Number: 1144297466
-Angelica