OPERATION IN DUSTY OR SANDY CONDITIONS.

TM5-4120-383-14

2-12.

OPERATION IN EXTREME

COLD.-Continued

e. When the unit is to be used at low temperatures in the COOL

mode, the low refrigerant pressure cutout switch must be jumped.

Contact organizational maintenance.

Be sure that all dampers are operating freely.

If unit is not being used or is being used in the HEAT mode

without fresh air, close (roll down) and secure the fabric cover.

OPERATION IN DUSTY OR SANDY CONDITIONS.

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. Some of the steps that may be taken are:

Frequent cleaning of filters, mist eliminator, coils and all

other areas of dust and sand accumulation.

In extreme conditions,

daily cleaning of filters may be necessary.

b. Limit the amount of dusty or sandy outside air introduced

through the fresh air damper to that essential for ventilation.

c. Roll down and secure the fabric cover on the back of the

cabinet during periods of shutdown.

OPERATION IN UNUSUALLY WET CONDITIONS.

The air conditioner is designed for normal exposure to the

elements, so it is reasonably waterproof. Some of the steps that

should be taken in an extremely wet climate are:

a. More frequent inspection and cleaning of the mist

eliminator condensate trap, and drain lines to insure proper

drainage and prevent accumulation of water inside the cabinet.

b. Roll down and secure the fabric cover on the back of the

cabinet during periods of wet, windy weather when the air

conditioner is not in operation.

c. Roll up and secure the fabric cover during dry weather when

the air conditioner is not in operation so that the interior can

dry out and condensation will not accumulate.

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