GB703953A - Improvements in and relating to gas-fired hot-water ready-supply devices combined with storage tanks - Google Patents

Abstract

703,953. Hot-water boilers. VAILLANT, H., [trading as VAILLANT-KOMMANDITGES., J.]. Jan. 9, 1952, No. 651/52. Class 64(1) [Also in Group XXIX] A gas-heated hot-water supply device, in which the water circulates between the heater and a storage tank and in which a shut-off device for interrupting normal circulation between the heater and tank is automatically actuated on tapping off hot water so that water leaving the storage tank is conducted through the heater for reheating before it reaches the outlet, is provided with a temperature-controlled valve regulating the flow from the tank to the heater so that the quantity of water to be reheated is smaller the lower its temperature. The heater comprises a water pipe 6 surrounding a flue 4 heated by a gas burner 5 and closed at the top by a block 7 traversed by the pipe. The pipe is connected to the storage tank 1 by upper and lower pipes 3, 2 providing continuous circulation for water heated to a predetermined storage temperature. The valve 22 controlling the supply of gas to the burner is under the control of a thermostat 24 in the tank (see Group XXIX). Cold water enters by a passage controlled by the valve 12 and hot water is drawn off by a pipe 18 and a valve 30. The normal circulation through the pipes 2, 3 can be interrupted by piston valves 8, 9 connected together by a rod 10, a downward extension of which is connected to the valve 12 and to a spring- pressed rubber diaphragm 11 dividing a control chamber 11' into upper and lower compartments. On opening the outlet valve 30, pressure in the lower compartment of the chamber 11<SP>1</SP>, caused by the inflow of water through the valve 12 and the restricted pipe 27 connecting to the tank, raises the diaphragm and causes the valves 8, 9 to close the pipes 2, 3. Water from the top of the tank thus flows via a pipe- 28 past a valve 14, Fig. 2 (not shown) which is under the control of a thermostat initially set by a hand-wheel to suit the required temperature of the issuing water, to the upper compartment of the chamber 11<SP>1</SP>, and through pipes 29, 6, 18 to the outlet. A temperature-sensitive element 19 in the pipe 18 provides additional control for the gas valve 22. In a modification, hot water is fed to the bottom of the storage tank and cooler water is circulated from the top.