TM 9-4120-407-14
3-7. PRELIMINARY SERVICING AND ADJUSTMENT OF EQUIPMENT.
a.
Check Installation.
(1) Check that air conditioner is securely mounted.
(2) Check that any gap around air conditioner and shelter wall is sealed against air and water
leakage.
(3) Check that the drains are open and if necessary, connected to drain lines.
b.
Check the Control Settings.
(1) Check that the control panel MODE selector rotary switch is in the OFF RESET position.
(2) Check that the potentiometer TEMPERATURE control is midway between the WARM and COOL
positions.
(3) Check that the circuit breaker has been placed in the ON (up) position.
c. Check Electrical Connections.
(1) Check that a grounding wire has been connected to the air conditioner casing and an appropriate
ground.
(2) Check that the power cable is connected to the air conditioner and a source of 208 volt, three
phase, 50/60 or 400 hertz electrical power.
(3) If the control panel has been remote mounted, check that the control cable is secure.
SECTION IV UNIT PREVENTIVE MAINTENANCE CHECKS AND
SERVICES (PMCS)
3-8. GENERAL. Systematic, periodic, preventive maintenance checks and services (PMCS) are essential to
insure that the air conditioner is ready for operation in any mode at all times. The purpose of a preventive
maintenance program is to discover and correct defects and deficiencies before they can cause serious damage
or complete failure of the equipment. Any effective preventive maintenance program must begin with the
training of operators to report all unusual conditions noted during daily checks or actual operation, to Unit
Maintenance. All defects and deficiencies discovered during maintenance inspections must be recorded,
together with corrective action taken, on DA Form 2404, Equipment Inspection and Maintenance Worksheet).
3-9. INSPECTION AND SERVICE.
a . Schedule. A schedule for unit preventive maintenance inspection and service should be established
immediately after installation of the air conditioner. A quarterly interval, equal to three calendar months
or 250 hours of operation, whichever occurs first, is recommended for usual operating conditions. When
operating under unusual conditions, such as a very dusty or sandy environment, it may be necessary to reduce
the interval to monthly or even less if conditions are extreme.
b. PMCS Instructions. Table 3-2 lists unit preventive maintenance checks and services that should be
performed at quarterly (or otherwise established) intervals. The PMCS items in the table have been
arranged and numbered in a logical sequence to provide greater personnel efficiency with the least amount of
required maintenance down time.
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