Patent GB-516525-A (GB)
Title: Improvements in hot water supply systems, and/or heating systems in which the heating medium is hot water
IPC: F24D11/00
Filed: 1938-06-02
Abstract: 516,525. Electrically - actuated valves. GRIFFITHS, E. E. June 2, 1938, Nos. 16474 and 21342. [Class 135] [Also in Group XIII] In a hot water supply or heating system, having a water heater 14 and feed tank 10, the latter is lagged and provided with additional pipe connections 21, 22, 25 and valves 23, 24, whereby surplus hot water obtained, due to low demand, or excessive supply of waste steam for heating the water heater 14, may be passed into the tank 10 for storage,.and subsequently fed to the heater 14 if an excessive demand occurs. The pipe 25 is hinged at 26, the upper end being kept near water level by a float 28, and the cold water inlet 11a may extend to the bottom of the tank. 'The valves 23, 24 may be operated electromagnetically under control of thermostats 29, 30 so that when the hot water is delivered at high temperature the valve 24 is opened and the valve 23 connects the pipes 17a, 19. When the hot water temperature falls, the valve 24 is closed, and the valve 23 connects the pipes 17a, 22. In a modification, Fig. 3, not shown, the valve 23 is close to the tank 10. In Fig. 5, the water heater 14a is heated by exhaust steam from a turbine 58 supplied by a boiler 60. The control valves 23, 24 are operated by a pressure sensitive device 61, which may alternatively be placed in the pipe 62, and may be responsive to velocity of the live or exhaust steam. In the latter case, a Venturi tube may be used to obtain pressure variations to operate the valves. Alternatively, a single thermostat with upper and lower temperature limits may be used. Fig. 4 shows a general arrangement of valves and controls. The valve 24 comprises a casing divided by a partition 34 with a series of ports 35 each having an independent closure member 36 actuated by an electromagnetic device 37. The valve 23 is connected to pipes 17a, 19, 22 as shown, and the casing is divided by two partitions 42, 43, with several independent valve members 46 actuated by electromagnets 47. The thermostats 29, 30 comprise a series of switches 49 connected to terminals 55, indicator lamps 57 and terminals 56 on a control panel. The terminals 56 are connected to the electromagnets 37, 47, so that a rising temperature causes successive openings of valves 36, and successive movements of valves 47 to open ports 45 and close ports 44. Corresponding indicator lamps 57 are energized. The valves 23, 24 may be operated by electric relays controlling the energization of the devices 37, 47. Fig. 6, not shown, illustrates such a relay control, associated with a water heater heated by live or exhaust steam. Alternative connections are provided by which the supply of steam to the water heater may be cut off at different temperatures. The valves 23, 24 may be operated by a combination of a time switch which closes at short intervals, and a. thermostatic reversing switch in series. Two or more systems of control, e.g., temperature and pressure, may be used. The storage of hot water may be controlled by a time switch, when electric heating is used, so that current may be used when cheapest.