7-15.2 Prestart procedures
Keep doors to ROWPU space and weatherdeck closed. Failure to do so overloads
HAC system and can lead to early failure.
Close doors to ROWPU space and weatherdeck and make sure they remain dosed when this system is being
Using vent handle extension stored in the dayroom, open HAC outlets in workshop and dayroom. Make sure they
are free from obstructions.
Using vent handle extension stored in dayroom, adjust round watertight ventilator outlets in deckhouse top of
workshop and dayroom.
Clean all components, including ventilator outlets, and make sure components are not damaged.
Close switchboard circuit breaker P5 to provide electricity to power panel 1.
Make sure power panel 1 circuit breaker 5P5 is dosed.
If AC unit is to be used and seawater pumps are NOT operating, set seawater valves as follows: (Figure 7-11)
Open SW3, SW27, SW28, SW35 and SW36.
If AC unit is to be used and seawater pumps ARE OPERATING, set seawater valves as follows: (Figure 7-11)
Open SW48, 47 and 28.
Close SW27 and SW3.
7-15.3 Operating procedures
7-15.3.1 AC unit
If seawater pumps are NOT operating, push black START button on AC cooling water pump controller on
centerline bulkhead in void 2 port. If seawater pumps ARE operating, do NOT activate AC cooling water pump.
Turn OFF/AC/HEAT selector switch to AC. Switch is on side of heating element above AC unit (Figure 7-9).
Turn AC electrical switch to ON (up position). Switch handle protrudes from AC unit in lower right comer of front
Turn left switch OFF/FAN/COOL to COOL (Figure 7-10) on AC controls on front of unit.
Turn right cooler switch on AC controls clockwise to obtain desired amount of cooling. (Clockwise increases
cooling, counterclockwise decreases cooling.) If unit has been operating within previous 30 minutes, a safety
delay switch may activate and AC compressor will not come on for 5 minutes.
System is thermostatically controlled and cycles on and off as necessary to maintain amount of cooling selected
with right-hand switch on AC controls. Check temperature indicated on thermometer in dayroom. Adjust cooler
switch on AC unit to maintain desired temperature.
Monitor seawater strainer 3 pressure shown on the two gauges activated by SW35 and SW36. If difference in
pressure is more than 2 psi, seawater strainer 3 must be switched and dogged basket cleaned. See
TM 55-1930-209-14&P-2, Seawater Systems, for these procedures.