GB1095265A - Continuous flow electric liquid heater - Google Patents

Abstract

1,095,265. Electric flow heaters. R. E. FRANCIS. April 2, 1965 [April 6, 1964], No. 14017/64. Heading H5H. [Also in Division H2] In a wall mounted domestic electric water heater controlled by a pressure switch 21, water flows through a coiled Cu heating tube 20 containing a heating element 31 comprising a resistance wire (31a), Fig. 3 (not shown) within a Cu tube (31b) filled with powdered MgO. Water enters an inlet pipe 17 containing an inlet valve 14 flows through a tapping 17a to the tube 20 and leaves through an outlet 12 containing a pressure relief valve. Pipe 17 is also connected to a diaphragm chamber of a pressure switch 21 (see Division H2) which operates a microswitch 27 controlling the electric supply to the heater and a neon pilot light 15 indicating when the heater is working. To increase heat dissipation and to stiffen tube 20 a wire 38 is wound around tube 31b and is arranged to touch the tube 20 forming a helical fin. The element extends longitudinally out of the ends of tube 20, water connections being made in the side of the tube. An overheat thermostat near the outlet and the pressure relief valve may operate de-energizing microswitches. The heater may comprise several tubes 20 in parallel and may be enclosed in a circular square or rectangular casing which may include a mirror, the tubes may form a shelf and the inlet valve may be positioned beneath the casing.