TM 9-4120-360-14
b. Inspection. Inspect the casing assembly for dents. gouges. cuts or tears. and major deformation. Remove
panels as necessary to determine whether internal components such as coils. wiring, piping or other components or
sub-systems have been damaged. If damage is apparent. leak-test all parts of the refrigeration system and make an
operating check of controls and functional components. If the unit is functionally OK. repair the casing.
c. Repair Straighten dents by using a sheet-metal hammer and back-up dolly, using care to avoid stretching the
metal more than necessary. Fill gouges with body putty. fiberglass-epoxy filler, or weld. Weld cuts or tears impossible, or
fabricate a patch and attach it with blind rivets. Sand paint to a feather edge around the repair, and paint as directed in TM
43-0139.
4.22. Insulation
a. Description. Insulation consists of sheets of foam plastic or foam rubber, attached with adhesive.
b. Inspection. Inspect insulation for areas of 1ooseness or separation from the metal panel, and for missing areas.
Replace damaged or missing insulation.
Acetone and methyl-ethyl ketone (MEK) are flammable, and their vapors are explosive. Prolonged
or repeated inhalation of fumes or contact with the skin can be toxic. Use in a well ventilated area,
wear gloves, and keep away from sparks or flame.
c. Removal. Scrape or pull off as much of the damaged insulation as possible. Soften the remaining insulation
and adhesive with acetone or MEK, and remove with a putty knife, paint scraper or similar tool. Repeat the softening and
scraping process as required, then clean up the metal surface with a cloth moistened in acetone or MEK.
d. Installation. Cut a sheet of the proper insulating material to the correct shape, and coat the attaching side with
adhesive. using a brush to ensure complete coverage. Also, brush adhesive on the metal to which the insulation is to be
attached. Let both surfaces air-dry until the adhesive become tacky but will not stick to the fingers. Starting at one corner
or at a narrow edge, carefully bring the insulation into full contact with the metal. Press into firm contact all over.
a. Description. The condensate drainage system consists of a drip pan, mounted beneath the evaporator coil,
and two tubes leading from the ends of the drip pan to the baseplate. The tubes are equipped with spring-loaded ball
check valves at their bottom ends, to prevent the bypassing of air through the tubes and around the evaporator intake. The
baseplate of the air conditioner is fitted with pipe-threaded holes for the attachment of standard plumbing fittings or hose
to conduct the condensate of a remote location.
b. Access. Since the condensate drainage system occupies both sides of the front of the air conditioner from top
to bottom, the top panel, lower panel and both evaporator grilles must be removed to the system. Also, the air filter and the
mist eliminator must be removed. Proceed as follows:
(1) Remove 18 screws and washers from the four edges of the fabric cover. and remove the fabric cover.
(2) Remove 15 screws and packing washers from the top surface of the top panel, and five screws through
the rear flange. Remove the top panel.
(3) Both the evaporator discharge and intake grilles are removed by turning six cam-lock studs in their
frames counter-clockwise to unlock them. Remove the grilles.
(4) Remove the mist eliminator by pulling it straight up.
(5) Remove the air filter by removing two screws from the retaining strip on the right-hand edge of the filter.
Pull the right-hand edge of the filter outward and to the right to remove it.
(6) Remove the lower panel by unscrewing the two panel fastener screws in the top edge. and pulling the
panel upward and out.
