Exception #2 in that article says to me that it is permissable to do it that way. But why leave it to chance? If it were me I would run (2) 15 amp dedicated branch circuits, one to each unit so if one stops working -- 20 years from now -- the other one will be working, and the customer won't be left without at least some heat, or A/C.
[This message has been edited by ShockMe77 (edited 01-04-2006).]
