Abstract: Valve bodies that are generally cylindrical and are open at top and bottom are combined with flow diverters which may be combined top to bottom to permit stacking of a combination of valves for actuation together without need for separator walls between valves. These elements, together with special adapters and end plates, permit economical manufacture of a series of manually or hydraulically actuated single and multiple function valves. These and other valve body and valve element forms and flow elbows are rendered more useful by the inclusion of seal retaining elements and flow turners.

Abstract: The efficiency with which the water in pools and spas may be heated is greatly improved by circulating water through a heat exchanger such that heated water is introduced at or near the lowest point in the body of pool or spa water and by removing water to be heated from a point near the surface notwithstanding that the heated water rises to form a warm layer at the surface. When the body of water is heated to a selected temperature, the flow direction is reversed so that water is withdrawn from the low point and, after heating, is returned to a point nearer the surface. That method has the advantage that it can be practiced with conventional pool and spa plumbing systems with minimum modification to permit a reversal of pool and spa inlet and outlet opening connection to the external water cleaning conduit. Water flow and control in the external circuit remains the same. System operation and practice of the method is enhanced by the inclusion of a solar energy collector and valves of unique design.

Abstract: Heating and cooling of dwelling houses and other confined spaces is facilitated by a system in which thermal energy is transported between an air heating and cooling system in the dwelling and a water heat storage sink or source, preferably in the form of a swimming pool or swimming pool and spa combination. Special reversing valve circuitry and the use of solar collectors and liquid-to-liquid heat exchangers on the liquid side of the system, and special air valves and air modules on the air side of the system, enhance the system's efficiency and make it practical in the sense that systems employing the invention can utilize existing craft skills and building financing arrangements and building codes, and the like, without major modification.

Abstract: A general purpose apparatus for measuring the chemical and physical state of flowing liquid materials and chemical additives and for introducing chemical materials to the stream uses a Venturi or other apparatus in which differential pressure is developed as an incident to fluid flow. It is arranged to be used both as a sample pump, a chemical additive pump, and as a differential pressure meter for use in calculating flow rates. The process method includes chemical addition at rates determined by pressure differential at the Venturi and for times which bear a selected relation to that differential pressure, temperature and the chemical state of the liquid. It also includes special temperature comparisons and flushing of chemical addition lines on an optional basis.