[VAC] Re: While on subject of A/C's.....

[Ray Plumlee <hrp41@xxxxxxxxx>]

Ken - the follow-up post by Jim Dunmyer on this subject gives a good
explaination of the intake/exhaust air flows on a typical window type
a/c unit - i used a 12k btu unit - the exhaust duct consisted of a
shallow sheet metal box attached to the rear of the unit - attached to
an opening in that i used a "rectangular to round" duct piece (found at
Lowes store) with a 90 deg bend and 8 " outlet - then attached a piece
of 8" round duct to go thru the floor and belly pan - i covered all
this duct work with insulating sheet material - as for the louvered
vents at the side to feed outside air across the condensor coil i
attached small rectangular ducts(with openings to match louvers)against
the sides of the unit and ran them thru the floor/belly pan - then
added a couple of drain tubes at low points in bottom of unit -
installed screnning in ducts at belly pan - don't know if in/out air
flow is correct but the thermal switch on the compressor has never
tripped - with a small fan at front of trailer to circulate air it does
a good job cooling the trailer - i could never get a straight/certain
answer from several HVAC people i asked as to what affect on a/c output
would be to let "cooled" inside air return thru the louvers on the
sides of the a/c case - i assumed it would reduce cooling capacity and
installed input ducting but am still uncertain that the extra work was
necessary - Ray Plumlee