Installation and Use

The insulated cabinet is a big factor in the success or failure of a refrigeration system. Heat leaks into a chilled box. This heat is what must be removed on a continuous basis. Energy usage or compressor amp draw is all based on the amount of cooling needed (heat leaking in). This energy usage is based on box size, the insulation type and thickness, and the climate the boat is in. Heat travels into the cabient from all directions so it is important to have a well insulated top and lid. Cold air will flow like water. All drains need to be plugged to prevent losing cold air. Lids require  good air seals.

Inside a refrigerated box, temperatures will be lower at the bottom. Mounting a cold plate at the top dools the warmer air and the box more evenly. Sometimes fans help even out the temperature.

Air is the medium that transfers the cooling  from the cold plate to the food. Shelves should be vented to allow air to flow. A grating or baskets should  be used to allow air to flow around the food. This is important in a freezer. Packing a boat refrigerator may require putting the lettuce at one end away from the cold plate  and the b eer rand milk at the bottom or near the plate.

Frost build up on cold plates will reduce the efficiency of the system. This frost is a product of humid conditions and wet products being refrigerated.

Technical Data*

 * For 24 volt operation, divide all amperage figures by half.

Energy Conversion Estimates

Compressor efficiency is about 3.5 to 4 BTU per watt in tropical climates. The BD compressors are variable speed; at low sppeds there is amp draw but a low cooling rate. HIgher compressor speed results in more cooling but more amp draw as well. Amp draw is therefore directly related to the amount of cooling being produced and is not the way to compare system performance.

A 2.3 CUbic foot (16' x 16" x 16') box with 3" of 2lb density foam insulation used as a refrigerator in the tropcis will use 25amp/hours @ 12 volts per day.

A 8 cubic foot (24" x 24" x 24") box with 3" of 2lb density foam insulation used as a refigerator in the tropics will use 57 amp/hours @ 12 volts per day.

A 15.6 cubic foot (30" x 30" x 30") box with 4" of 2lb density foam insulation used as a refrigerator in the tropics will use 68 amp/hours @ 12 volts per day.