Swamp coolers, also called evaporation coolers, covert evaporating water into air and provide natural means of cooling. Air 15°-40°F cooler than the outside temperature is then directed into the home, and the warmer air is pushed out through the vents. Size and Selection
Before determining the size, count and location of the ducts you need to determine the right model of swamp cooler that fits your needs. The size and cooling capacity of swamp coolers is measured in cubic feet per minute (cfm). Most models of swamp coolers range in size between 3,000 and 25,000 cfm. The selection of right swamp cooler for your house not only depends on the size of the cooler but also on the size of the vicinity or space the cooler is required to cover and on the levels of heat and humidity that affect your living conditions.
For instance, If you live in a hot, dry climate such as in Southern California and your home floor area is 1,200 square feet, a 5,000 cfm swamp cooler will be sufficient to cool your home. If you live in regions of moderate heat and humidity, a 12,00 square feet may need no more than 4,000 cfm swamp cooler to function sufficiently.
Most swamp coolers do not need a duct installation. Swamp coolers smaller in size can be often fitted into the wall windows, much like a regular portable air conditioners, and therefore require very little installation. Also, you can just open door and windows to other rooms for air to circulate around and within the house.
Larger units require ducts to circulate the air in and out of the house. You can either use already existing air duct system in the house or install new ducts for air circulation. Ducts can be installed either on the walls, ceiling or on the floor provided there is a back-end channel for hot air to leave the house.
Ducting Size and Location
This duct vents comes in three sizes– 18, 20, and 24 inches. Use 18 inch for coolers 4500 cfm or smaller, 20 inch for up to 5500 cfm, and 24 inch for 6500 cfm coolers.These sizes will fit between most ceiling or attic trusses. Do nor install the duct work at the peak or ridge of the roof. Keep the duct outlets to the bare minimum. Swamp coolers dump a lot of water into the air stream. This makes the air heavy. If you have multiple outlets, air will thin out and very little air will actually reach the destination rooms.
A person installing the ducting system should have basic knowledge of electrical wiring, plumbing and ducting. Ducting work primarily involves sizing and cutting the flexible ducts or tunnels that streamline the air from the cooler toward the duct openings. This can be done on the ground, then lifted up into place from the attic, or dropped down from the roof. Be precise in measuring the length ans size of the flexible duct, and also the size of the venting grills that will push air into the house. Also, Calculate for the internal plumbing and electric wiring structuring before you begin the ducting work. Make sure the duct openings do not damage the overall structural integrity of the roof or the attic ceiling.