Abstract: A multi-function fluid flow monitoring apparatus capable of measuring fluid flow-related variables of fluid in a channel on the basis of signals from any one or more of a plurality of different types of flow sensors. Such different types of flow sensors may include, for example, a bubbler-type pressure sensor, a submerged pressure transducer, an ultrasonic transducer, and/or a velocity sensor forming part of an area-velocity sensor system, each of which sensors may be selectively connected to the apparatus as needed to accommodate various monitoring conditions. The apparatus is further capable of monitoring various conditions of fluid in the channel, such as pH level, ORP, temperature, solution conductivity, dissolved oxygen, and the like.

Abstract: A solid fuel burning hot water heater is described having a primary combustion chamber with a refractory material base portion which forms the locus of combustion. A water jacket defines an upright portion over the refractory base portion for receiving a charge of fuel in a generally vertical stack. The water jacket is coupled to a source of water for at least convection circulation and assists in confining the locus of solid fuel combustion to the base of the chamber. Heat exchange channels or pathways are defined around the outer periphery of the water jacket in heat exchange relationship with the water jacket for transfer of heat from the end products of combustion to the circulating water. A flue gas delay channel arrangement extends from the draft outlet at the base of the combustion chamber to the heat exchange pathways.