Heating and ventilating system

Claim 1

IN A SYSTEM FOR CONDITIONING AIR, THE COMBINATION COMPRISING, AN ENCLOSURE FORMED BY A ROOF AND A PLURALITY OF WALLS, A HOUSING HAVING A FRONT WALL DISPOSED WITHIN AN OPENING IN ONE WALL OF SAID ENCLOSURE, MEANS DIVIDING THE INTERIOR OF SAID HOUSING INTO UPPER AND LOWER COMPARTMENTS, A FURNACE DUCT OPENING ON ONE HAND THROUGH SAID FRONT WALL INTO SAID ENCLOSURE AND DIRECTED ON THE OTHER HAND INTO SAID LOWER COMPARTMENT, HEATING MEANS WITHIN SAID DUCT, A DISCHARGE NOZZLE THROUGH SAID FRONT WALL FOR DIRECTING AIR FROM SAID UPPER COMPARTMENT INTO SAID ENCLOSURE, FAN MEANS PROPELLING AIR FROM SAID UPPER CHAMBER THROUGH SAID NOZZLE AND INTO SAID ENCLOSURE, SAID DIVIDING MEANS INCLUDING ADJUSTABLE FIRST DAMPER MEANS FORMING THE SOLE PASSAGE BETWEEN SAID TWO COMPARTMENTS FOR SELECTIVELY REGULATING THE VOLUME OF AIR RECIRCULATED BY SAID FAN MEANS FROM THE ENCLOSURE THROUGH THE DUCT AND LOWER COMPARTMENT INTO THE UPPER COMPARTMENT AND THROUGH THE DISCHARGE NOZZLE, SECOND ADJUSTABLE DAMPER MEANS DISPOSED WITHIN AN OPENING THROUGH THE REAR WALL OF SAID HOUSING FOR SELECTIVELY REGULATING THE ADMISSION OF OUTSIDE AIR INTO SAID UPPER COMPARTMENT, BY SAID FAN MEANS, ADJUSTING MEANS INTERCONNECTING SAID FIRST AND SECOND DAMPER MEANS WHEREBY MOVEMENT OF SAID ADJUSTING MEANS IN ONE DIRECTION CLOSES ONE OF SAID DAMPER MEANS WHILE OPENING THE OTHER OF SAID DAMPER MEANS, WHEREIN, BY ACTUATION OF SAID ADJUSTING MEANS SAID TWO DAMPER MEANS MAY BE POSITIONED TO REGULATE THE PROPORTIONAL VOLUME OF OUTSIDE AIR ADMITTED INTO SAID UPPER COMPARTMENT FOR ADMIXTURE WITH THE AIR BEING RECIRCULATED THERETHROUGH FROM SAID LOWER COMPARTMENT PRIOR TO DISCHARGE BY SAID FAN MEANS INTO SAID ENCLOSURE THROUGH SAID DISCHARGE NOZZLE, AND AN ADJUSTABLE AIR EXHAUST DAMPER IN ONE WALL OF SAID LOWER COMPARTMENT COMMUNICATING WITH THE OUTSIDE AIR FOR MAINTAINING THE AIR PRESSURE IN SAID ENCLOSURE AT A PRESELECTED LEVEL.