SECTION II. EQUIPMENT DESCRIPTION AND DATA

TM 55-1905-223-24-17

SECTION II. EQUIPMENT DESCRIPTION AND DATA

1-6.

General Description. The environmental control subsystem, also referred to as HVAC (heating,

ventilation, and air conditioning), provides heating and/or cooling of air taken into the ship and air

circulated within the ship. The subsystem maintains a clean, comfortable atmosphere in the living and

working spaces, and provides air flow in other spaces to maintain proper temperature and ventilation.

Spaces that produce excessive heat, such as the engine rooms, auxiliary machinery rooms, and galley

areas; and vapor-producing spaces such as flammable liquid storerooms and paint mixing rooms, are

served by the supply and exhaust ventilation systems, which vent to the outside air. The subsystem is

an integrated system of fans, air conditioning and heating units, piping and ducting, and controls that

are manually started and thermostatically control the subsystem.

1-7.

Characteristics, Capabilities, and Features. The environmental control subsystem equipment,

shown in FIGURE 1-1, is the equipment required to heat, ventilate, and air condition the living and

working spaces aboard the vessel.

Heating System. The heating system consists of duct heaters, unit heaters, and convection

heaters.

(1)

Duct Heaters

Flanged type, mounted in supply air ducts

Metal sheath electric heating elements

Manual and automatic start

Thermostat controlled

Manual and automatic reset

Thermal cutouts

Heaters over 48 amps are individually fused

Liquid proof terminal box/sealed joints

(2)

Unit Heaters

Self-contained, continuous duty space heaters

Wall or ceiling bracket mounted

Electric heating coils

Forced air (fan)

Manually operated

Paint locker heaters fitted with explosion proof motor

Manual and automatic reset

Built-in time delay fan

Built-in thermostat and controls

Built-in thermal overload protection

Totally enclosed unit

(3)

Self-contained space heaters

Wall mounted

Electric heating coils

1-2