Pressurized hot water heating system having auxiliary pressurizing vessel

Claim 1

IN A CLOSED HOT WATER HEATING SYSTEM COMPRISING A BOILER AND RADIATION MEANS CONNECTED TO SAID BOILER IN A CLOSED CIRCUIT INCLUDING SUPPLY AND RETURN LINES FOR SAID RADIATION MEANS, A PUMP FOR CIRCULATING WATER THROUGH SAID CLOSED CIRCUIT, AN AUXILIARY PRESSURIZING VESSEL INCLUDING A CONNECTION THEREFROM TO SAID CLOSED CIRCUIT, SAID AUXILIARY PRESSURIZING VESSEL BEING ADAPTED TO RECEIVE EXPANDED WATER FROM SAID SYSTEM UPON THE EXPANSION OF WATER IN SAID SYSTEM AND TO RETURN WATER TO SAID SYSTEM UPON CONTRACTION OF WATER IN SAID SYSTEM, SAID PRESSURIZING VESSEL CONTAINING THE WATER THEREIN IN A NORMALLY QUIESCENT FASHION UNDISTURBED BY CIRCULATION IN SAID CLOSED CIRCUIT AND HAVING MEANS FOR MAINTAINING THE LIQUID THEREIN UNDER PRESSURE, AND VALVE MEANS IN SAID CONNECTION AND INTERMEDIATE SAID PUMP AND SAID AUXILIARY PRESSURIZING VESSEL FOR DETERMINING WHETHER SAID AUXILIARY PRESSURIZING VESSEL IS CONNECTED TO THE SUCTION OR DISCHARGE SIDES OF SAID PUMP, SAID VALVE MEANS INCLUDING A FIRST CONNECTION TO THE SUCTION SIDE OF SAID PUMP, A SECOND CONNECTION TO THE DISCHARGE SIDE OF SAID PUMP, A VALVE ACTUATING MEMBER MOVING IN RESPONSE TO PRESSURE CONDITIONS AT SAID PUMP TO ALTERNATELY CONNECT SAID AUXILIARY PRESSURE VESSEL TO SAID FIRST AND SECOND CONNECTION.