Question:
I live in the desert southwest where swamp coolers are prevalent. Lately,
more and more homes are being built with
refrigerated air (due to water concerns, efficiency, etc...) and I'm
wondering just how hard would it be to retrofit
my house with a refrigerated air unit? There are probably a million
details to be understood but I'm really looking
for any advice on this. Most companies are charging a fortune for the unit
and install labor so I was thinking that maybe
I could do the install myself and save some money. I assume it would tie into
the existing ductwork but I'm wondering if these
things require return air or do they just pull from their location outdoors?
Any other gotcha's with this project?
Answer:
What you are seeing when you say you aren't seeing any return is a
LARGE duct that is carrying both the return air AND the cooled/heated
air. The most typical retrofit in Arizona was to remove a roof
mounted cooler and install a roof mounted AC unit. The main
difference was that a return duct had to be provided so the duct
opening in the roof that was already there was simply enlarged to
accommodate the large double duct.
Keep in mind two things. The swamp cooler blows a LOT of air and the
ducts were sized for that air volume. When you retrofit you don't
need to use as large a connection between the actual blower in the AC
and the existing ductwork in the house compared to what was needed for
the swamp cooler. So the space taken by the original swamp cooler
cooled air duct is already oversized. That allows the AC connecting
duct for the out air to be reduced to something smaller then what the
swamp cooler had and helps make space for the return duct the AC will
need and that the cooler didn't have.
The setup you have is obviously different since the swamp cooler is
slab mounted. You'll still need a return duct but without knowing
your exact setup now there's no way to say what options you might
have. Ideally the return duct will be ceiling height and in the
hallway. You could accomplish that by simply running an entire new
duct up the side of your house, thru the upper side of the house/roof,
and over to where your hall ceiling is.
