GB1433355A - Central heating control apparatus - Google Patents

Abstract

1433355 Central heating systems A LINS 4 May 1973 [5 May 1972] 21379/73 Heading F4U A central heating system comprises a boiler 1, a domestic hot water tank 2, a heating circuit including radiators 4, and a control device (Fig. 2) which includes within a housing 20, a circulating pump 12, a temperature-responsive changeover valve 13, a temperature-responsive mixing valve 14 as well as flow and return connections 5-10 for the boiler, the heating circuit and the heat exchanger 3 in the tank 2. In operation of the system, the changeover valve 13 closes off the heat exchanger return 10 (as shown in Fig. 2) when enough domestic hot water is stored in tank 2 so that pump 12 then feeds the heating medium (usually water) only through the circuit of the boiler 1, the mixing valve 14, the radiators 4 and the valve 13. Depending on the adjustment of the temperature-dependent means of the mixing valve 14, either a proportion of the returning heating medium is fed back directly via the mixing pipe 11 into the flow of heating medium passing through connection 7 (attached to chamber 21) to the radiators 4, or pipe 11 is closed off and all of the returning heating medium passes into the boiler 1. When the domestic water in tank 2 is to be heated, then by means of valve 13, the heating connection 8 is closed (disc and seating 27 coming together) and connection 10 opened. During this time, no water flows through the radiators 4 or through connection 7. If mixing valve 14 opens to connect pipe 11 to connection 5, a proportion of the returning heating medium may pass into the tank 2 through connection 9. The temperaturedependent closure means of the valves 13, 14 may be removed from their respective chambers as single units.