Abstract: A geyser pump and a geyser pumped heat transfer system having a multitude of heat absorbing tubes from which heated liquid is pumped into a vapor/liquid separator by geyser action enhanced by positive vapor bubble generation apparatus and flow control methods. A vapor condenser in communication with the separator recovers heat contained in the vapor bubbles and maintains low separator pressure. Pumping starts and stops in response to temperature differences and the pumping rate is proportional to the heating rate. For bubble generation a small volume of the working fluid is isolated in good thermal contact with the absorbing tube and an aperture is formed in communication between the isolated volume and the main volume of working fluid. The small volume of working fluid can be enclosed by inserting into the geyser pump tube a device in the form of a flanged cylinder or a U-shaped tube. Vapor forms readily in the isolated volume and a vapor.+-.

Abstract: A self-pumping solar heating system having a collector including a multitude of small diameter riser tubes from which heated liquid is pumped into a header by a geyser action. A vapor condenser assures a header pressure conducive to bubble nucleation in the riser tube upper end segments. The level of liquid within the header or its outlet is higher than the liquid level in the riser tubes to produce a gravity imbalance capable of circulating heated liquid past a storage heat exchanger, below the header, and then upwardly through the closed vapor condenser in the header prior to return to a collector inlet manifold. A modified header utilizes an open vapor condenser in vapor communication with the collector header.

Abstract: A continuous HCl in-air indicator consists of a tube-like element with an inlet end through which a continuous stream of air, containing HCl, enters. The air flows downstream from the inlet end and exits the element's outlet end. Positioned between the element's inlet and outlet ends are first and second spaced apart photoelectric units, which are preferably positioned adjacent the inlet and outlet ends, respectively. Ammonia gas is injected into the air, flowing through the element, at a position between the two photoelectric units. The ammonia gas reacts with the HCl in the air to form ammonium chloride particles. The difference between the outputs of the two photoelectric units is an indication of the amount of HCl in the air stream.