OPERATION IN EXTREME HEAT. - TM-5-4120-364-130022

TM 5-4120-364-13

b. If cooling air is desired at lower ambient (outside) temperatures, set the selector switch knob to the

"VENTILATION position to operate the blowers only.

2-6.

OPERATION IN EXTREME HEAT.

NOTE

Unit preventive Maintenance Checks and Services (PMCS) should be performed at daily

intervals.

a. General. The air conditioner is designed to operate in temperatures up to 120F (49C). Extra care should be

taken to minimize the cooling load when operating in extreme high temperatures.

b. Protection.

(1) Check all openings in the enclosure, especially doors and windows, to be sure they are tightly closed. Limit

in and out traffic if possible.

(2) When appropriate, use shades or awnings to shut out direct rays of the sun.

(3) When possible, limit the use of electric lights and other heat producing equipmenr-

(4) Limit the amount of hot, outside air introduced through the fresh air damper to that essential for ventilation.

NOTE

Weatherstripping, the installation of storm doors, and windows, if appropriate, and

insulation of surfaces exposed to the outside is recommended when operating in

extremely high temperatures for extended periods.

c. Cleaning.

(1) Clean outside grilles, coils, filters, and mist eliminator more frequently.

2-7.

OPERATION IN DUSTY OR SANDY CONDITIONS.

NOTE

Unit Preventive Maintenance Checks and Services (PMCS) should be performed at daily

intervals.

a. General. Dusty and sandy conditions can seriously reduce the efficiency of the air conditioner by clogging the

air filter, mist eliminator, and coils. This will cause a restriction in the volume of airflow. Accumulation of dust or sand in the

condenser coil and/or in the compressor compartment may cause overheating of the refrigeration system. Dust or sand may

also clog the condensate trap and water drain lines.

CAUTION

Never operate the air conditioner without having the air filters in place.

b. Protection.

(1) Shield the air conditioner from dust as much as possible.

(2) Take advantage of any natural barriers which offer protection.

(3) Limit the amount of dusty or sandy outside air introduced through the fresh air damper.

(4) Roll down and secure the fabric cover on the back of the cabinet during periods of shutdown.

c. Cleaning.

(1) Keep the air conditioner as clean as possible.

(2) Pay particular attention to the outside grilles, condenser, filters, mist eliminator, louvers, and electrical

components.

(3) In extreme conditions, daily cleaning of condenser, filters, and outside grilles may be necessary.

2-8.

OPERATION UNDER RAINY OR HUMID CONDITIONS.

The air conditioner control panel must be protected to prevent direct contact with rain or heavy moisture.

2-9.

OPERATION IN SALT WATER AREAS.

a. Exposure to salt water and air may cause corrosion of exposed metal surfaces.

b. Wash down the exterior of the unit with clean fresh water at frequent intervals. Take care not to damage

electrical components with water.

c. Inspect the unit daily and clean the evaporator and condenser coils and air filter as often as required to maintain

proper operation.

* U.S. GOVERNMENT PRINTING OFFICE: 1991 554-123/20264

PIN:

047288-002

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