Gas burner control

Claim 1

IN A BURNER CONTROL SYSTEM, A BURNER, A FUEL SUPPLY CONDUIT TO SAID BURNER, FIRST AND SECOND ELECTROMAGNETICALLY OPERATED VALVES IN SAID SUPPLY CONDUIT ARRANGED IN SERIES, SAID FIRST VALVE BEING OPERATIVE BETWEEN FULLY OPEN AND FULLY CLOSED POSITIONS AND SAID SECOND VALVE BEING OPERATIVE BETWEEN FULLY OPEN AND PARTIALLY CLOSED POSITIONS, SAID FIRST VALVE HAVING A NORMALLY FULLY CLOSED POSITION WHEN DE-ENERGIZED AND SAID SECOND VALVE HAVING A NORMALLY PARTIALLY CLOSED POSITION WHEN DE-ENERGIZED, AND WHEN IN SAID PARTIALLY CLOSED POSITION WHEN DE-ENERGIZED TO RESTRICT THE FLOW OF FUEL TO THE BURNER, A SOURCE OF POWER, AN ENERGIZING CIRCUIT FOR SAID VALVES INCLUDING A FIRST, HIGH-TEMPERATURE THERMOSTAT RESPONSIVE TO A DROP IN THE TEMPERATURE OF THE SPACE BEING HEATED BELOW A FIRST PREDETERMINED POINT OF CLOSE AND COMPLETE THE ENERGIZATION AND EFFECT THE OPENING OF SAID FIRST VALVE AND A SECOND, LOW-TEMPERATURE THERMOSTAT RESPONSIVE TO A DROP IN THE TEMPERATURE OF THE SPACE BEING HEATED BELOW A SECOND, LOWER, PREDETERMINED POINT TO CLOSE AND COMPLETE THE ENERGIZATION AND OPENING OF SAID SECOND VALVE BUT ONLY IF SAID FIRST, HIGH-TEMPERATURE THERMOSTAT IS CLOSED, THE CIRCUIT ARRANGEMENT BEING SUCH THAT SAID FIRST VALVE IS CONNECTED ACROSS THE SOURCE OF POWER THROUGH SAID FIRST, HIGH TEMPERATURE THERMOSTAT AND SAID SECOND VALVE IS CONNECTED ACROSS THE SOURCE OF POWER THROUGH SAID FIRST AND SECOND THERMOSTATS IN SERIES, AND A CURRENT LIMITING CONDUCTOR CONNECTED ACROSS SAID SECOND, LOW-TEMPERATURE THEMOSTAT, SAID CURRENT LIMITING CONDUCTOR HAVING SUCH RESISTANCE VALVE AS TO PERMIT SUFFICIENT ENERGIZATION OF SAID SECOND ELECTROMAGNETICALLY OPERATED VALVE WHEN SAID SECOND THERMOSTAT IS OPEN TO HOLD SAID VALVE OPEN ONCE IT IS OPEN, WHILE, ON THE OTHER HAND, RESTRICTING ENERGIZATION SUFFICIENTLY WHEN SAID SECOND THERMOSTAT IS OPEN TO PREVENT ACTUATION OF SAID SECOND VALVE FROM ITS NORMAL PARTIALLY CLOSED POSITION TO ITS FULLY OPEN POSITION, WHEREBY WHEN THE SPACE IS BEING HEATED FROM A COLD CONDITION THE MAXIMUM FLOW OF FUEL TO THE BURNER WILL PERSIST UNTIL THE SPACE TEMPERATURE HAS REACHED THE POINT WHEREIN SAID FIRST, HIGH-TEMPERATURE THERMOSTAT OPENS, EVEN THOUGH SAID SECOND, LOW-TEMPERATURE THERMOSTAT HAS PREVIOUSLY OPENED AT A LOWER SPACE TEMPERATURE.