Abstract: The invention relates to an integrated thermostatic control system for cooling and heating. The control system includes cooling and heating valves and fluid pressure controlled operating elements for the valves. The system has a common sensor and a common variable chamber temperature setting unit. A capillary tube system connects the operating elements to the sensor and the temperature setting unit. An adjustable spring associated with either of the operating units biases the associated valve in the closing direction to provide an operationally dormant dead zone.

Abstract: In an air conditioning system having both a hot deck for heating air and a cold deck for cooling air, both decks being supplied by a supply duct, a control system is disclosed for minimizing the total cost of heating the air in the hot deck and cooling the air in the cold deck by measuring the amount of heating done in the hot deck and deriving the heating cost therefrom, measuring the amount of cooling done in the cold deck and deriving the cooling cost therefrom, and controlling the temperature of the air in the supply duct until the heating cost equals the cooling cost to thereby minimize the total heating and cooling costs.

Abstract: Thermostat control of separate heating and cooling apparatus is achieved with a system that requires only a two-conductor connection between the thermostat and the apparatus. A pair of oppositely-poled diodes is employed at each end of one of the conductors of the connection so that when the control system is established, by a selector switch, in the heating mode the half cycles of one polarity of an AC voltage effect the operation of the heating apparatus, whereas when the system is switched to the cooling mode the opposite polarity half cycles cause operation of the cooling apparatus. The invention is especially advantageous when a central air-conditioning system is added to a building where only a two-wire cable connects the thermostat to the existing heating system. Rewiring of the thermostat cable is unnecessary.

Abstract: A thermostat adapted for controlling heating and cooling apparatuses has a temperature control point adjustment means connected to a changeover switch means whereby upon the adjustment of the temperature control point adjustment means in a first range to select a cooling point, the changeover switch means only connects the thermostat to the cooling apparatus and when the temperature control point adjustment means is in the heating range, the changeover switch means only connects the thermostat to the heating apparatus. The limited range of temperature selection in the first and second range is an energy conservation feature of the thermostat.

Abstract: The heating and cooling system for a multiple coil installation includes a bypass passage or conduit provided with a check valve which is closed when the pump of either the heating circuit or the cooling circuit is energized and which is opened when the pumps of the heating circuit and the cooling circuit are not energized whereby a third pump which operates continuously, is effective when the check valve is open to continuously circulate the water in a closed path through the bypass circuit which is interconnected to the inlet and outlet sides of the multiple coil installation, thus bypassing the heating and cooling circuits.

Abstract: An electronic temperature control system utilizes a circuit having two main terminals for connection to a low voltage relay control system of the type generally used in residential heating or cooling systems without the need for an auxiliary source of power. The circuit includes a temperature sensing thermistor, an adjustable reference voltage control, a programmable unijunction transistor voltage threshold detector circuit, power switching thyristor means and bridge diodes. Heat anticipation is provided by thermally coupling the thyristor switching means and the temperature sensing thermistor.

Abstract: A novel control circuit for heating and heating/cooling systems wherein in a heating mode the circuit controls a valve means comprising a main valve and a modulating valve through which gas is supplied to a burner. The main valve is a normally closed, solenoid-actuated type which opens when its coil is energized, and energization of its solenoid is controlled by a pair of normally open relay contacts connected in series. One of the contacts closes when the temperature in the space being heated drops below a preset temperature. The other contact remains closed so long as the temperature in the space being heated remains below a maximum limit. In a heating/cooling system the circuit is selectively operatively coupled with the valve means and a refrigeration unit. When heating is selected, the circuit operates as mentioned above. In cooling, a cooling solenoid of the refrigeration unit is energized when the temperature in the space being cooled rises above a preset temperature.

Abstract: An air conditioning system for conditioning air in a plurality of enclosed areas in a building. Conditioned air at a relatively cold temperature level is supplied to a terminal for discharge into an area. The quantity of relatively cold temperature air discharged into the area is regulated in accordance with the temperature level therein. A control signal is generated, the magnitude thereof being indicative of the quantity of conditioned air discharged into the area. The magnitude of the control signal is monitored. Warm air supply means is activated when the magnitude of the control signal indicates that the quantity of the relatively cold temperature air being discharged into the area has decreased below a predetermined level.

Abstract: An air conditioning system for conditioning air in a plurality of enclosed areas in a building. Conditioned air at a temperature level which may be varied is supplied to first terminal means for discharge into an area. Conditioned air at a relatively constant temperature level is delivered to second terminal means for discharge into the area. The quantity of constant temperature air discharged into the area is regulated in accordance with the temperature level therein. When the temperature of the variable temperature air supply is at a relatively warm level, the quantity thereof discharged into the area is regulated in accordance with the quantity of constant temperature air discharged into the area. As the quantity of constant temperature air discharged into the room is increased, the quantity of warm air discharged into the room is decreased; and as the quantity of constant temperature air discharged into the room is decreased, the quantity of warm air discharged into the room is increased.

Abstract: A heat exchange system having a source of heat exchange output fluid for effecting a heat exchange function and having a source of return fluid resulting from the output fluid providing its heat exchange function. A thermally operated element controls the amount of flow of the output fluid from the source in relation to the temperature of the thermally operated element. A sensing device senses the temperature effect of the heat exchange function in relation to a predetermined temperature that the heat exchange system is to provide, the sensing device directing one of the output fluid and the return fluid to the thermally operated element to cause the same to change the amount of flow of the output fluid when the temperature effect deviates from the predetermined temperature a certain amount whereby the thermally responsive element is subject to a relatively wide swing in temperature for large control movement thereof in relation to a relatively narrow swing in temperature at the sensing device.

Abstract: A heat exchange system having a source of heat exchange output fluid for effecting a heat exchange function and having a source of return fluid resulting from the output fluid providing its heat exchange function. A thermally operated element controls the amount of flow of the output fluid from the source in relation to the temperature of the thermally operated element. A sensing device senses the temperature effect of the heat exchange function in relation to a predetermined temperature that the heat exchange system is to provide, the sensing device directing one of the output fluid and the return fluid to the thermally operated element to cause the same to change the amount of flow of the output fluid when the temperature effect deviates from the predetermined temperature a certain amount whereby the thermally responsive element is subject to a relatively wide swing in temperature for large control movement thereof in relation to a relatively narrow swing in temperature at the sensing device.

Abstract: A heat exchange system having a source of heat exchange output fluid for effecting a heat exchange function and having a source of return fluid resulting from the output fluid providing its heat exchange function. A thermally operated element controls the amount of flow of the output fluid from the source in relation to the temperature of the thermally operated element. A sensing device senses the temperature effect of the heat exchange function in relation to a predetermined temperature that the heat exchange system is to provide, the sensing device directing one of the output fluid and the return fluid to the thermally operated element to cause the same to change the amount of flow of the output fluid when the temperature effect deviates from the predetermined temperature a certain amount whereby the thermally responsive element is subject to a relatively wide swing in temperature for large control movement thereof in relation to a relatively narrow swing in temperature at the sensing device.

Abstract: A heat exchange system having a source of heat exchange output fluid for effecting a heat exchange function and having a source of return fluid resulting from the output fluid providing its heat exchange function. A thermally operated element controls the amount of flow of the output fluid from the source in relation to the temperature of the thermally operated element. A sensing device senses the temperature effect of the heat exchange function in relation to a predetermined temperature that the heat exchange system is to provide, the sensing device directing one of the output fluid and the return fluid to the thermally operated element to cause the same to change the amount of flow of the output fluid when the temperature effect deviates from the predetermined temperature by a certain amount whereby the thermally responsive element is subject to a relatively wide swing in temperature for large control movement thereof in relation to a relatively narrow swing in temperature at the sensing device.

Abstract: A space thermostat for controlling the two-stage operation of both heating and cooling apparatus includes two single-pole, double-throw mercury type switches operatively connected to a single bimetallic coil. One switch energizes stage one of the heating apparatus when tilted in one direction and energizes stage two of the cooling apparatus when tilted in the other direction. The other switch energizes stage two of the heating apparatus when tilted more in the direction which effected the energizing of stage one of the heating apparatus and energizes stage one of the cooling apparatus when tilted less in the direction which effected the energizing of stage two of the cooling apparatus. The switches are adjustably mounted with respect to each other so that the differential between stages can be adjusted to be the same as the differential of each switch.

Abstract: A heat exchange system having a source of heat exchange output fluid for effecting a heat exchange function and having a source of return fluid resulting from the output fluid providing its heat exchange function. A thermally operated element controls the amount of flow of the output fluid from the source in relation to the temperature of the thermally operated element. A sensing device senses the temperature effect of the heat exchange function in relation to a predetermined temperature that the heat exchange system is to provide, the sensing device directing one of the output fluid and the return fluid to the thermally operated element to cause the same to change the amount of flow of the output fluid when the temperature effect deviates from the predetermined temperature a certain amount whereby the thermally responsive element is subject to a relatively wide swing in temperature for large control movement thereof in relation to a relatively narrow swing in temperature at the sensing device.

Abstract: A motor control apparatus having an electric motor which is driven in one direction by an alternating current power source and in a return direction by a spring return wherein a holding or braking of the motor is accomplished by the application of a source of direct current power to magnetize the motor and hold it in a predetermined intermediate position after the removal of the alternating current power source. The braking or holding action is removed by taking away the direct current power source and momentarily applying an alternating current power source to the motor to de-magnetize or degauss the motor so it is free to return to its initial condition under the power of the spring return.

Abstract: An automatic temperature responsive control valve is disclosed for use in combination heating and cooling systems including two concentric valve sleeves each rotating individually in the valve body under the control of respective bimetallic transducers one of which directs work fluid to either a heating heat exchanger or a cooling heat exchanger in accordance with the temperature of work fluid supplied to the valve by either a chiller or a boiler through a solenoid valve controlled by the outside temperature and the other of which provides modulated flow through the heating or cooling means under the control of the spent fluid temperature. The control valve is usable for controlling the temperature of one or more rooms or for similar control of a process vessel so as to provide unique versatility of use.

Abstract: An air conditioning system for conditioning air in a plurality of enclosed areas in a building. Conditioned air at a temperature level which may be varied is supplied to first terminal means for discharge into an area. Conditioned air at a relatively constant temperature level is delivered to second terminal means for discharge into the area. The quantity of constant temperature air discharged into the area is regulated in accordance with the temperature level therein. When the temperature of the variable temperature air supply is at a relatively warm level, the quantity thereof discharged into the area is regulated in accordance with the quantity of constant temperature air discharged into the area. As the quantity of constant temperature air discharged into the room is increased, the quantity of warm air discharged into the room is decreased; and as the quantity of constant temperature air discharged into the room is decreased, the quantity of warm air discharged into the room is increased.

Abstract: An air conditioning system for conditioning air in a plurality of enclosed areas in a building. Conditioned air at a relatively cold temperature level is supplied to a terminal for discharge into an area. The quantity of relatively cold temperature air discharged into the area is regulated in accordance with the temperature level therein. A control signal is generated, the magnitude thereof being indicative of the quantity of conditioned air discharged into the area. The magnitude of the control signal is monitored. Warm air supply means is activated when the magnitude of the control signal indicates that the quantity of the relatively cold temperature air being discharged into the area has decreased below a predetermined level.

Abstract: A three-way changeover valve construction having a housing means provided with an inlet and a pair of outlets. A pair of valve seats are carried by the housing for respectively controlling fluid flow from the inlet through the outlets. A pair of valve members are provided for respectively controlling the valve seats with the valve members being operatively associated together to move substantially in unison relative to the valve seats in response to a condition sensed by a condition responsive device. A changeover device is operatively associated with the valve members to position the same to act respectively on one side of the pair of valve seats or on the other side of the pair of valve seats to change the valve construction from a cooling function thereof to a heating function thereof in response to a temperature change in the flowing medium.

Abstract: .Iadd.A thermostat for controlling heating apparatus is converted to a thermostat for controlling heating and cooling apparatus by the addition of a subbase. The heating thermostat has a double switch attached to a bimetal and a heating anticipation heater whereby heating apparatus is controlled when connected to the terminals of the thermostat. When it is desired to use the thermostat to control both heating and cooling apparatus, the thermostat is removed from the wall and a subbase is placed under the thermostat. The subbase has a cooling anticipation heater which is thermally connected to the bimetal. The subbase has terminals to connect the assembly of thermostat and subbase to the heating and cooling apparatus. .Iaddend.