A complete Cruisair air conditioning system requires the control/switch assembly, the seawater cooling system, and the air distribution system.
Controls. Cruisair has two basic types of controls, digital Q-Logic controls and mechanical rotary-knob switch assembly.
- The Q-Logic controls, featuring the Qht or Q3 keypad/displays, are part of a microprocessor system with many advanced functions, including automatic fan speed control, fault display, and a dehumidification program. Decorative bezels can be added to Q-Logic display/keypads to match your interior design.
- A rotary-knob switch is a manual control with two or three knobs offering control over mode of operation, thermostat, and variable fan speed. Reverse-cycle models have automatic changeover between heating and cooling.
Seawater System. The seawater cooling system consists of an inlet through-hull fitting, seacock (water valve), strainer, pump, and overboard discharge fitting, all connected by hose or piping.
If multiple air conditioning units are served by a single seawater pump, then a pump relay and water manifold are required. Cruisair recommends a centrifugal seawater pump for efficient, quiet operation and long life. Centrifugal pumps are not self-priming and must be mounted below the water-line.
It is important that the seawater plumbing be “self-draining”, meaning that if the boat is lifted, all water in the piping will drain out. An air conditioning system plumbed this way will have no air locks which could disrupt the flow of seawater.
For shallow-draft boats where it is impossible to mount the pump below the water-line, a self-priming pump must be used.
| Fig. 1: Typical Seawater Plumbing System |
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- Air Distribution Systems. Cabin air is drawn into the selfcontained unit or air handler through a return air grille. It is then cooled or warmed and blown back into the cabin through a ducting system. The air should be discharged high in the cabin and away from the return air grille to ensure good circulation. Plenums (transition boxes) can be installed in the ducting to allow multiple discharge grilles, in one or more cabins. Insulated duct is recommended to prevent secondary condensation. An air filter, located on the cooling unit or on the return air grille, must be cleaned regularly.
| Fig. 2 Typical duct installation beneath a settee |
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Fig. 3 Comparison of typical remote and self-contained systems |
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