I recently took a vacation to Arizona, and I noticed many of the
single family homes have a small packaged conventional Cooling Unit
(with electric heat in it I assume) coupled with a Swamp Cooler
tied into the same supply duct as is visible from the outside .
My question is : Is there some type of damper arrangement at each
unit that will prevent the supply air of one unit that is operating
from escaping thru the other unit which is dormant ? And, is this
controlled thru automatic controls within the dwelling ? Maybe an
HVAC guy from the Southwest can enlighten us on this setup. Thanks.