GB1362534A - Hot water heating system - Google Patents

Abstract

1362534 Hot water heating and supply systems MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 20 July 1971 [23 July 1970 (4)] 34072/71 Headings F4U and F4A [Also in Division G4] A hot water heating system comprises a burner 2 for heating in a heat exchanger 3 water which is supplied through an upstream passage 1b and a fluid flow control device 7 to either a central heating radiator 5 through an outlet 11 or to a heat exchanger 13<SP>1</SP> through an outlet 12 for heating draw-off water flowing through a duct 14 to a draw-off point 15 prior to recirculation to the heat exchanger 3 under the impetus of a pump 4 in a downstream passage 1a. The device 7 operates by the Coanda effect and comprises a supply port 9 from the passage 1b which is formed with a nozzle 8 leading into an intermediate zone 10 from which the outlets 11, 12 lead, and a passage 13 leads a controlling amount of water from the passage 1b to either of the outlets in response to the temperature of the hot water in the passage 1b as sensed by a bellows device 23 which operates a valve member 25. The difference in pressure of the draw-off water in the duct 14 above and below the heat exchanger 13<SP>1</SP> is used via lines 35, 36 to position a diaphragm 32 in a water pressure responsive device 28 which operates a valve 24 controlling water entry to the control passage 13 and thereby flow of hot water to the heat exchanger 13<SP>1</SP>. A further water pressure responsive device 68 controls flow of fuel to the burner 2 by measuring the water pressure difference above and below the device 7, which difference is transmitted via lines 75, 76 to a diaphragm 72 controlling the position of a valve 63 in the gas supply line. Further control of the gas supply to the burner is effected by a temperature sensitive valve 62 controlled by a bellows device 66 in response to a temperature probe 69 positioned within the passage 1b.