Installation Guidelines for Direct Expansion Air Handler

When choosing the porper model Direct Expansion Air Handler unit, primaru consideration should be given to calculated BTU loads and available power supply.

Direct Expansion Air Handler units are ductable and designed to be installed in low cabin areas(under berths, lockers, etc.) and ducted to high supply air grilles. These units have rotatable blower-motor assemblies providing flexibility to fit specific space requirements and allowing for proper duct work installations. Transition boxes may be used to supply air to more than one area from a single unit.

Securely fasten the air handler to a solid, level surface using the vibration isolating mounts provided. Rotate and scure the blower, if necessary, to its porper position to provide the most direct routing of the ducting to transitions and supply grilles. Route all ducting to transitions and supply air grilles. Route all ductiong as smooth and straight as possible. Trim off excess ducting before making final connections. Secure the ducting every 48" (minimum) to prevent movement while the vessel is underway.

The return air inlets must be properly sized and located to allow adequate return air flow to the unit. All return air grilles must have removeable filters to trap dust and other airborne particles. If return air grilles are not used, a clip-on type of filter mest be attached to the air handler unit. Return air grilles should not be located in such a way as to allow the supply air to blow directly into the opening. This will cause "short cycling" of the unit resulting in poor performance.

The supply air grilles must be sized and located to allow for proper circulation within the cabin area(s). Grilles located close to the ceiling or directed upwards provide for the best air circulation. Undersized grille, along with crushed or kinked duct work, will result in poor or inadequate performance.

Never install your air conditioner air handler in bilge or engine room area. Insure that the selected location is sealed from direct access to bilge and/or engine room vapours. Do not terminate condensate drain lines within four (4) feet of any outlet of engine or generator exhaust systems, nor i in a compartment housing an engine or generator, nor in a bilge (vapours can travel up the drain line), unless the drain is connected properly to a sealed condensate or shower sump pump. Failure to comply may allow bilge or engine room vapors to mix with the air conditioners return air and contaminate living areas.

Both condensate drain lines must be connected to the evaporator blower's two drian pan spuds, using reinforced flexible hose(5/8") and clamps. The drains may be teed together, providing there is a minimum drop of 2" from the drain pan to the tee fitting. Properly secure the drain lines to prevent movement or lifting during vessel operation. Check the drains upon completion by pouring two quarts of water into the drain pan.

Refrigerant-grade copper tubing should be properly sized for the specific application. Both the suction and liquid lines should be insulated seperately with approved closed cell foam jackets (i.e. Rubatex 1/4" wall thickness). The refrigerant line ends should remain capped until the actual connections are made to prevent contamination. Avoid any kinks in the tubing as this will compromise the perfomrmance and longevity of the system. Use approved flareing techniques and refrigerant grade components for all components for all connections. Insulate all fittings using cork insulation tape or foam tape (only after system has been leak-checked). Wrap fittings sufficiently to the equal R-value of tube insulation.

The installed line sets and evaporator(s) must be evacuated to remove air from these components and prevent moisture acidity formation. All connections should be properly leak-checked upon releasing the refrigerant charge from the condensing unit into the system. If the system is to be opened for any reason at this point, or for future service, the refrigerant charge must be "pumped down" back into the condensing unit or "recovered" using proper equipment to prevent escape into the atmosphere. In accordance with EPA regualtions, only certified technicians should perform service on, or make adjustments to, the circuit.

All wiring must be sized according to marine design standards. Only stranded tinned copper wire is to be used. All units must be properly grounded and bonded.