Winterizing ZR6 with "optional drain kit?

[Quinner]

I would also question 2 & 6, why they need them if only 3 & 5 are connected to the quick drain?? Would be interested to see if any water came out of 2 & 6 after using the quick drain.

[poecs13]

I wondered that too, but sure enough, my test yielded no water after using the quick drain.