Note the location of the two air-conditioning coolers, or evaporators, in the crew's quarters and the after machinery compartment. The cooling coils are readily accessible for cleaning. The compressors are located in the pump room.

Part of the system is a suction main that exhausts fumes and used air, and part is a pressure main through which fresh or conditioned air is blown into the compartments. Small arrows on Figure 18-1 indicate the direction of air flow in these ducts;

Dampers, located at most of the inlet and exhaust points of the ducts, are manually set to control the rate of air flow into and out of the rooms at such points.

18A2. Insulation of ducts. The supply air ducts are insulated to prevent heat gain during passage of the newly conditioned air to the rooms. The supply ducts in the engine room and the supply ducts from the discharge side of the forward air-conditioning cooler to the after bulkhead of the forward torpedo room are provided with 1/2-inch insulation. All other mains and branch ducts are cork painted.

The submarine ventilation supply is provided by one motor-driven fan, located in the forward machinery compartment, that delivers air through the two evaporators, or air-conditioning coolers, to the various room outlets of the ducts at the maximum rate of 4,000 cubic feet per minute. The exhaust ventilation through air ducts is provided by another motor-driven fan located in the forward machinery compartment. This forced exhaust ventilation through ducts is not provided in the after torpedo room and maneuvering room, from which exhaust air flows through bulkhead ventilators. The individual rates at which the air is exhausted and delivered in the various compartments is shown in Figure 18-1.

18A4. Ventilation data. The following table shows, for each room, or compartment, the net volume in cubic feet, the air supplied in cubic feet per minute, and the number of minutes required to change the air in the room.