Heating or cooling system for heat exchangers

Claim 1

AN AIR TEMPERATURE CONTROL SYSTEM COMPRISING, IN COMBINATION, MEANS DEFINING AN AIR FLOW PATH, A FLUIDTRANSFER MEDIUM HEAT EXCHANGER AND AN ELECTRIC HEATER WITHIN SAID FLOW PATH, MEANS SELECTIVELY SUPPLYING SAID HEAT EXCHANGER WITH A HEATING OR A COOLING MEDIUM, MEANS FORCING AIR THROUGH SAID FLOW PATH, AN INLET AND AN OUTLET PASSAGE ASSOCIATED WITH SAID HEAT EXCHANGER, A BY-PASS CONDUIT ESTABLISHING COMMUNICATION BETWEEN SAID INLET AND OUTLET PASSAGES BY-PASSING SAID HEAT EXCHANGER, AN ELECTRICALLY OPERATED VALVE LOCATED WITHIN ONE OF SAID PASSAGES AND COMMUNICATING WITH SAID BY-PASS CONDUIT SELECTIVELY CLOSING SAID CONDUIT AND PERMITTING FLOW THROUGH SAID HEAT EXCHANGER, AND OPENING SAID CONDUIT ESTABLISHING COMMUNICATION BETWEEN SAID PASSAGE AND PREVENTING FLOW THROUGH SAID HEAT EXCHANGER, AN ELECTRIC HEATER CIRCUIT INCLUDING A FIRST SWITCH MOVABLE BETWEEN FIRST AND SECOND POSITIONS, AN ELECTRIC VALVE CIRCUIT INCLUDING A SECOND SWITCH MOVABLE BETWEEN FIRST AND SECOND POSITIONS, A FLUID-TRANSFER MEDIUM TEMPERATURE-SENSING CIRCUIT INCLUDING A THIRD SWITCH MOVABLE BETWEEN FIRST AND SECOND POSITIONS, FLUID MEDIUM TEMPERATURE-SENSING MEANS OPERATIVELY ASSOCIATED WTIH SAID THIRD SWITCH POSITIONING SAID THIRD SWITCH TO SAID FIRST POSITION UPON A COOLING MEDIUM BEING SUPPLIED TO SAID VALVE AND POSITIONING SAID THIRD SWITCH TO SAID SECOND POSITION UPON A HEATING MEDIUM BEING SUPPLIED TO SAID VALVE, AIR TEMPERATURE-SENSING MEANS OPERATIVELY ASSOCIATED WITH SAID FIRST AND SECOND SWITCHES, AND FIRST SWITCH IN SAID FIRST POSITION BEING IN SERIES WITH SAID THIRD SWITCH IN SAID FIRST POSITION ENERGIZING SAID ELECTRIC HEATER, SAID SECOND SWITCH IN SAID FIRST POSITION BEING IN SERIES WITH SAID THIRD SWITCH IN SAID SECOND POSITION ENERGIZING SAID VALVE CLOSING SAID CONDUIT TO FLUID FLOW AND DIRECTING FLUID THROUGH SAID HEAT EXCHANGER, SAID FIRST SWITCH IN SAID SECOND POSITION BEING IN SERIES WITH SAID SECOND SWITCH WHEN IN SAID SECOND POSITION, THEREBY ENERGIZING SAID VALVE AND DIRECTING A COOLING MEDIUM THROUGH SAID HEAT EXCHANGER WHEN SAID THIRD SWITCH IS IN SAID FIRST POSITION.