Abstract:
A thermostatic air conditioner control for use with individual unit air conditioners having a thermostatic switch disposed at a location remote from the air conditioner. The control includes circuitry interposed between the air conditioner and a source of electrical energy operative a selected time interval after closure of said thermostatic switch to energize a socket in which the air conditioner is plugged, and operative a selected time interval after opening of said thermostatic switch to de-energize the socket.
Abstract:
An air conditioning system wherein the functions of heating, cooling, humidifying, dehumidifying, ventilation, and natural cooling are automatically controlled during all types of weather by standard control instruments including an indoor 4-stage thermostat, an outdoor thermostat, and two humidistats, programmed in coordinated functional sequence through electrical control circuits and relays.
Abstract:
A temperature control system which utilizes a two-level pneumatic pressure source and a control valve operative to selectively subject the control system to either of the two pressure levels or to a pulse of decreased pressure to effect normal night temperature, warm-up period temperature, and normal day temperature modes of operation.
Abstract:
An air-conditioning system for a zone is disclosed which includes air-heating and air-cooling apparatus which are cycled for heating or cooling air moving to the zone through a duct. Cycling of the apparatus is governed by a temperature control system including a zone air temperature sensor and a duct air temperature sensor. The duct sensor has a relatively large authority in affecting control of the air-conditioning apparatus when the heating or cooling load on the zone is light so that variations in the duct air temperatures alone can effect cycling of the apparatus without any appreciable variation in the zone air temperature from a set point temperature. The authority of the duct sensor diminishes substantially when the zone temperature is relatively remote from the set point so that the conditioning apparatus is not cycled according to the duct air temperature.
Abstract:
A refrigeration system for a room air conditioner having an outside heat exchanger with two separate refrigerant flow passages connected either directly or through an expansion device as controlled by a reversing valve. One of the passages is substantially more restrictive than the other. The reversing valve is responsive to the room temperature so that when full capacity cooling is required, the valve directs refrigerant flow from the first passage to the substantially more restrictive second passage and then through the expansion device so that the heat exchanger functions as a normal condenser; however, when reduced capacity cooling is desired, the valve directs refrigerant flow from the first passage, through the expansion device, then through the second restrictive passage which passage than functions similar to an evaporator and reduces the cooling capacity of the system. Further, with this arrangement, the reduced capacity operation permits a reduction of power for driving the compressor. Controls to stop and start the compressor and to control the valve are also provided along with an evaporator having multiple inlets to prevent freezeup when the system is operated continuously.
Abstract:
A pneumatic pressure responsive apparatus utilizing diaphragm logic which selects and transmits the lowest pressure of a plurality of input pressures.
Abstract:
A zone-type heating, cooling, dehumidifying air-conditioning system is shown wherein each zone or unit is provided with a primary heat exchanger circuit and a secondary heat exchanger circuit. The primary heat exchanger is arranged to be supplied with warm water during the heating season and chilled water during the cooling season. The secondary heat exchanger is arranged to be supplied with domestic warm water. Each of the heat exchangers is provided with a control valve for controlling the circulation of heat exchange liquid therethrough. A fan is arranged to circulate air of the respective zone serially in heat exchange relationship with the primary heat exchanger and the secondary heat exchanger. A zone control system responsive to the temperature and humidity of the respective zone and the temperature of the heat exchange fluid being supplied to the heat exchangers controls the operation of the valves. Where domestic warm water is used for obtaining dehumidification, an overriding control prevents the use of domestic warm water for dehumidification in excess of the supply to thereby maintain the desired domestic warm water temperature.
Abstract:
1280686 Air conditioning plant ITT INDUSTRIES Inc 29 July 1969 [2 Aug 1968] 38024/69 Heading B1T [Also in Divisions F4 and F3] In an air conditioning plant, a filter unit comprises fibre glass or dense foam filter mats 47 or a filter blanket passed between rollers. A warning light is actuated when the set of filter mats or the filter roll requires replacement in response respectively to a device for measuring the pressure difference between opposite sides of the mats and to a limit switch actuated near the end of the roll. A fan 53 draws air through the filter unit.
Abstract:
1,038,020. Air conditioning; heating and cooling buildings. SVENSKA FLAKTFABRIKEN A.B. Dec. 21, 1964, No. 51927/64. Headings F4V and F4U. In an induction type air conditioning system secondary air is treated in the heat exchangers mounted in the induction units before mixing with primary air and the liquid medium supplied to these heat exchangers is maintained at a temperature common for the whole plant and lower than the temperature of the secondary air, the temperature of the primary air being regulated in dependence on the outdoor conditions. In Fig. 4, 1 designates the heat exchangers within the induction units, 2 a heat exchanger forming part of the central air conditioning plant and 3 pipe lines forming a closed circuit between heat exchangers 1 and 2. 4 and 6 are circulation pumps, pump 6 maintaining through a by-pass line 7 a constant liquid flow through the heat exchanger 2 regardless of the number of heat exchangers 1 being used. During winter, heat is supplied by heated primary air, but in order to eliminate simultaneous cooling by the heat exchangers 1, the heated medium is passed to heat exchanger 2 through which the primary air 5 is taken in. In order to prevent moisture forming on heat exchangers 1 the medium is maintained at a temperature which is above the dew point temperature of the room air by introducing into the circuit a quantity of heated medium from a separate heat source at 8 and withdrawing a corresponding quantity of the medium at 9. In order to maintain, during fluctuations of outdoor air temperature, the medium at a desired temperature quantities of warm or cold medium are added to the circuit, the warm medium added as previously described and the cold medium added at 12 with a corresponding quantity discharged at 13. When the ventilating air 5 is too hot to cool the medium in heat exchanger 2, the medium is maintained at the desired temperature solely by the cold medium supplied at 12, circuit 3a, Fig. 5. If in this case, should the ventilating air also require cooling, a separate cold medium supply line 19 is used regulated by valve 20 which is governed by thermostat 22 located in the air flow 5, the cold medium passing straight to the heat exchanger 2 around circuit 3b. Any warm or cold medium added to the circuit is always added to the circuit immediately after the corresponding quantity has been withdrawn.