The difference might be hose shape as well so hopefully the longer one is right. Looking at the diagram I would say that if there is only three hoses going to the heater valve then there can't be coolant flowing with the heater valves closed. I think if you search there is a really nice colour pic on how all that works if you want to make sure.

__________________
1988 325is (purchased new) sold
2004 X5 3.0 2005 X3 2.5
2008 X5 3.0 (new to me)