Abstract: A rectangular, flexible duct serves as an alternative to galvanized sheet metal duct work installed in homes by utilizing corrugated semi-rigid top and bottom walls with relatively flexible connecting side walls so that the duct may be easily rolled and stored. But when unrolled, it is fastened, for example, between floor joists of a home by use of an overhanging flange formed by one of the top or bottom walls. The duct walls are made of heat resistant plastic suitable for heating and ventilating. Rigidity is provided in the top and bottom walls by corrugations or ribs formed in the plastic.

Abstract: An improved gas-fueled ceramic tile burner capable of maintaining a stable flame at very high surface heat loading of a high porosity ceramic body. The improved ceramic tile burner includes a coarse steel mesh which is positioned abutting the downstream side of the ceramic body and upon which a pressurized mixture of air and fuel is ignited. The mesh helps to generate gas regeneration zones which stabilize the flame. Optionally, the disclosed ceramic tile burner has a secondary retaining mesh below the ceramic body which can be connected to the coarse steel mesh and to a burner housing in order to ground the meshes.

Abstract: A coupled dual loop absorption system which utilizes two separate complete loops. Each individual loop operates at three temperatures and two pressures. This low temperature loop absorber and condenser are thermally coupled to the high temperature loop evaporator, and the high temperature loop condenser and absorber are thermally coupled to the low temperature generator.