TM 9-4120-357-14
CHAPTER 6
GENERAL SUPPORT MAINTENANCE INSTRUCTIONS
6-1. General.
Repair of operating components of the air conditioner is achieved by replacing parts. Information on replacement
procedures is contained in Chapters 4 and 5. Repair instructions for the casing and insulation are included here for ref-
erence.
6-2. Insulation and Gaskets.
a. Disassemble the air conditioner only to the extent necessary to obtain access to damaged insulation or gaskets.
b. Using a putty knife, paint scraper or similar tool, scrape as much of the insulation or gasket to be replaced from
the structural surface as possible.
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WARNING
Acetone and methyl-ethyl ketone (MEK) are extremely flammable, and their va-
pors are explosive when mixed with air. Also, they are slightly toxic upon pro-
longed breathing or contact with the skin. Use in a well ventilated area, avoid ex-
cessive inhalation or contact with the skin, and take precautions against sparks or
open flame.
c. Using a cloth or sponge, saturate the residual insulation and adhesive with acetone or MEK until soft. Scrape the
softened residue from the structural support with a wood or fibre blade. Repeat, if necessary, until bare metal is ex-
posed.
d. Obtain a replacement part of insulation, or locally manufacture a section or patch from the same kind of material.
Lay it on a flat surface with the attaching side up. Brush a coat of adhesive on the exposed surfaces.
e. Brush a coat of adhesive on the metal surface to which the insulation or gasket is to be attached. Let the adhe-
sive dry until it is tacky but will not stick to the finger when touched.
f. Starting with one corner, attach one edge of the insulation to its place on the casing. Hold the opposite side
away from the casing, and progressively press the insulation into contact until it is all attached.
g. Reassemble the air conditioner as required.
6-3. Sheet-Metal Parts
NOTE
Cuts, tears or punctures in the casing or panels must be repaired to prevent by-
pass leakage of air. Leakage will severely reduce operating efficiency.
a. Disassemble the air conditioner only to the extent necessary to expose the damaged area for repair.
b.
Remove insulation from the area to be
repaired. (Refer to
Paragraph 6-2.)
_________
WARNING
Toxic fumes are emitted by burning or overheated insulation, and heated refrig-
eration piping can burst with explosive force. Shield wiring and piping, and re-
move insulation in the area if weld-repair is necessary.
c. Repair damage, using standard sheet-metal repair procedures as necessary. Rivet or weld patches to the inside
surface when required.
6-1