Abstract: A multi-bag supporting stand useful for efficient sand bagging operations has a base, a vertical support extending from said base, and a dual bag holder frame slideable along the vertical support for adjusting the height of the bag support frame for differently dimensioned bags. In one embodiment, the dual bag holder is expandable to a quadruple bag holder by attachment of single bag holder modules. Both the dual and single bag holders are adjustable for different bag widths, and each includes bag supporting hooks from which bags may be hung.

Abstract: In lieu of passing all air to be conditioned over an evaporator coil which is cold enough to cause a substantial amount of water vapor to condense; only a portion of the air is cooled to this extent. The remaining air is cooled to a higher temperature (at which negligible water vapor condenses). The total work to recompress the vaporized refrigerant is thereby reduced.

Abstract: A bed of beads is placed in the path of the air flowing to the tubing of the condenser. Water is sprayed on the bed so that it will be evaporated and so cool the air below the dry bulb temperature.