Abstract: A valve control device includes a receiving unit, an opening degree control unit, and a fixing control unit. The receiving unit receives information concerning the measured temperature of a fluid to be cooled that is cooled by a vaporizer in a refrigerant circulation path that is equipped with the vaporizer and a condenser. The opening degree control unit variably controls the opening degree of a valve that controls the flow rate of the refrigerant that circulates through the circulation path in accordance with the difference between the measured temperature and a target temperature provided in advance. The fixing control unit fixes the opening degree of the valve with priority over variable control performed by the opening degree control unit in the case where a fixing condition based on the difference between the measured temperature and the target temperature and a valve opening degree variation condition is satisfied.

Abstract: A process for producing ammonia and a derivative of ammonia from a natural gas feed comprising conversion of natural gas into a make-up synthesis gas; synthesis of ammonia; use of said ammonia to produce said derivative of ammonia, wherein a portion of the natural gas feed is used to fuel a gas engine; power produced by said gas engine; is transferred to at least one power user of the process, such as a compressor; heat is re-covered from exhaust gas of said gas engine; and at least part of said heat may be recovered as low-grade heat available at a temperature not greater than 200° C., to provide process heating to at least one thermal user of the process, such as CO2 removal unit or absorption chiller; a corresponding plant and method of modernization are also disclosed.

Abstract: An HVAC system within a building including an HVAC device having a blower fan, a number of sensors, and a control device. The control device has a processor that is configured to receive a request to operate the blower fan. The control device is further configured to determine an air quality value based on measurements provided by the sensors, and a runtime of the blower fan within a previous time frame. The control device is also configured to operate the blower fan based on the determined air quality value and the determined runtime of the blower fan within the previous time frame.

Abstract: The invention relates to a method for adjusting a cryogenic refrigeration apparatus including a plurality of liquefiers/refrigerators arranged in parallel in order to cool a single device. The method includes a step of calculating in real time the dynamic mean value of at least one operating parameter for all the liquefiers/refrigerators. The apparatus controlling in real time the at least one valve for controlling the stream of working gas of at least one liquefier/refrigerator in accordance with the difference between the instantaneous values of the parameter relative to said dynamic converge toward said dynamic mean value.

Abstract: A method for controlling a coupled heat exchanger system having a first heat exchanger block and a second heat exchanger block. A first fluid stream is divided into a first partial current and a second partial current both flowing through the heat exchanger system. A second fluid stream flows through the first heat exchanger block counter to the first partial current. A third fluid stream flows through the second heat exchanger block counter to the second partial current. An intermediate temperature is measured on one of the heat exchanger blocks. The amount of the first partial current and the second partial current is controlled based on the current value of the intermediate temperature. This control reduces the strain on the heat exchangers by changing loads while keeping fluctuations of the intermediate temperature low.

Abstract: An argon reflux condensation system and method in which a plurality of once-through condensers are connected to an argon column of an air separation plant to condense argon-rich vapor streams for production of reflux to the argon column. Condensation of the argon-rich vapor streams is brought about through indirect heat exchange with crude liquid oxygen streams that partially vaporize and are introduced into a lower pressure column of the plant for further refinement. The flow rate of the crude liquid oxygen streams are sensed and controlled at locations in the air separation plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Prior to flowing into the once-through condensers, the partially vaporized crude oxygen stream enters a phase separator which separates the crude oxygen vapor from the crude liquid oxygen.

Abstract: According to an embodiment of the disclosure, a retrofit for a system using a fluid to transfer thermal energy in a system that utilizes a thermostat to regulate a temperature associated with a terminal is provided. The retrofit includes a return line temperature sensor configured to measure a temperature of a fluid leaving a terminal; and a circuit. The circuit is configured to: receive a signal from a thermostat, the signal commanding a modulated valve to open or close; receive a temperature from the return line temperature sensor; determine whether the temperature is either greater than a maximum set point or less than a minimum set point; and modify the signal from the thermostat if the temperature is either greater than the set point or less than set point.

Abstract: Exemplary embodiments relate to a system and method for monitoring functional operational reliability of a cooling system having at least one thermosyphon for transformers provided with at least one evaporator and with at least one condenser. The cooling system using a coolant which can be vaporized and a gaseous medium, as a heat carrier.

Abstract: Method of controlling a variable delivery pump fitted to a heating system comprising: a heat exchanger connected to two circuits of fluids, the variable delivery pump making it possible to vary the flow-rate of the first fluid inside the heat exchanger; a return loop on the primary circuit allowing the first fluid reaching the input of the heat exchanger to mix with a portion of the first fluid coming from the output of the exchanger; a first temperature sensor measuring a temperature of the second fluid coming from the secondary circuit; a second temperature sensor measuring a temperature of the first fluid coming from a primary circuit; a control unit electrically connected to the first and second temperature sensors, the sensors generating electrical signals as functions of the temperatures and constituting electrical input signals of the control unit.

Abstract: A secondary pump-type heat source system includes: heat sources connected in parallel; a load system in which the heat source water flows; a primary pump supplying the heat source water to the load system; a secondary pump provided for each heat source and supplies the heat source water subjected to heat exchange in the load system to the heat source; and a heat source controller calculating flow quantity of the heat source water flowing in the heat source side and flow quantity of the heat source water flowing in the load system side by assigning a result from measurement by a water temperature sensor detecting heat source temperature to an operating characteristic of each heat source and controlling operation of the secondary pumps based on the calculation result.

Abstract: An electronic device can be provided with a housing having at least one wall defining a cavity and a flow sensor at least partially contained within the cavity. The flow sensor may be configured to detect a flow characteristic related to the flow of a fluid through a first portion of the cavity. The electronic device may also include a processor configured to alter a performance characteristic of the electronic device based on the detected flow characteristic.

Abstract: In order to provide a method of operating a solar thermal power plant, in which a heat transfer medium is evaporated endothermally by solar radiation in an evaporator section, wherein the evaporator section comprises a plurality of evaporator branches, among which the heat transfer medium is distributed, in which method non-uniform radiation conditions of the evaporator section may be effectively taken into consideration, it is provided that the mass flow distribution at the evaporator section is controlled, wherein the mass flows are adjusted individually at all or a majority of the evaporator branches and a controlled variable is a variable characterizing a spatial energy rise in a respective evaporator branch in a region of the evaporator branch where the heat transfer medium has not yet evaporated.

Abstract: A method operates a heat exchanger unit and determines a current physical characteristic of a process fluid at or adjacent a process fluid outlet of the heat exchanger unit and predetermining a desired physical characteristic of the process fluid at which the process fluid is desired to exit the heat exchanger unit. If the current physical characteristic of the process fluid is greater than the desired physical characteristic of the process fluid, then either a current fan speed is incrementally increased or the current fan speed is set at a predetermined low set point fan speed. Alternatively, if the current physical characteristic of the process fluid is less than the desired physical characteristic of the process fluid, then either the current fan speed is incrementally decreased or the current fan speed is set at a predetermined high set point fan speed or an OFF operating mode is activated.

Abstract: A system for operating a cooling loop associated with a space and including at least one cooling coil and cooling fluid supply, the system including: a grain sensor positioned with respect to the space and providing a value indicative of the amount of moisture in the space; at least one pump fluidly coupled across the coil; at least one flow limiter fluidly coupled to the coil and limiting a flow of cooling fluid between the cooling fluid supply and the coil; and at least one controller electrically coupled to the flow limiter; wherein, the at least one controller selectively operates the flow limiter responsive to the value indicative of the amount of moisture in the space and the pump re-circulates cooling fluid independent of the cooling fluid supply dependently upon the flow limiter.

Abstract: Methods for optimizing a thermocline in a thermal energy storage fluid within a thermal energy storage tank are disclosed. The methods comprise identifying a thermocline region in the fluid, adding thermal energy to a fluid stream extracted from the thermocline region, and returning the fluid stream to the tank at a plurality of locations above the thermocline region. The methods further comprise regulating the temperature of the fluid returned to the tank at a set point temperature by modulating the flow rate of the fluid stream and by changing the location from where the fluid is extracted from the tank.

Abstract: Temperature-control system used for heating or cooling in a method for controlling temperature of a component includes connected temperature-control device, temperature-control arrangement, supply line, and return line. The system additionally has a controller having a valve, an actuator, a supply temperature sensor, and a return temperature sensor. A temperature difference between the supply temperature and the return temperature of a fluid circulating in the system is registered using the supply temperature sensor and the return temperature sensor and also a regulator. Proceeding from this temperature difference, the regulator causes the actuator to set a degree of opening of the valve so the temperature difference is in a selected value range. The valve always has a minimal degree of opening in the open state.

Abstract: An apparatus for cooling N heat-producing devices, where AT is an integer no smaller than one, using a cooling fluid that may be supplied at a temperature below the dew-point temperature of ambient air. To avoid condensation on the heat-producing devices, the cold fluid is warmed, upstream of the heat-producing devices, to a temperature T0 that is above the dew-point. The warming is accomplished, in a heat exchanger, by the warm fluid returning from the heat-producing devices. The amount of warming is controlled by periodically measuring T0 as well as the N temperatures downstream of the N heat-producing devices, and sending these N+1 temperature measurements to a control element that implements a control algorithm whose purpose is to achieve a set-point value of T0 by regulating, via N control valves, the flow of fluid to the N heat-producing devices. Also provided is a method for cooling the N heat-pro during devices pursuant to the inventive apparatus by a temperature control over the cooling fluid.

Abstract: A brewing process including taking off a fluid having a starting temperature from a heat store; feeding the fluid to a plurality of heat consumers for releasing heat; and returning to the heat store the fluid which has a final temperature. The brewery installation has a heat store for controlling the flow of the fluid in the installation, and a plurality of heat consumers each of which is connected to the primary circuit for releasing heat. Improved efficiency is achieved in part by the final temperature of the fluid which flows out of the respective heat consumers is measured and the return of the fluid is controlled as a function of the measured final temperature.

Abstract: A method is provided for adjusting several parallel connected heat exchangers supplied with a coolant medium. The aim of the invention is to simplify the adjustment. For this purpose, the method consists in a) determining a specific value of heat requirement for each heat exchanger in a predetermined time period; b) comparing the specific values of all heat exchangers therebetween and c) in modifying the adjustment of the heat exchanger having the lowest specific value of heat requirement in such a way that the heat requirement thereof is increased.

Abstract: An electronic apparatus rack which can prevent the degradation of cooling performance due to local heat concentration on the exhaust side of the server. The electronic apparatus rack having electronic apparatuses mounted thereon, consists of a radiator incorporated in the rear door of the electronic apparatus rack; plural fans installed on the exhaust side of the radiator; and plural heat pipes installed on the intake side of the radiator.

Abstract: Sensing, actuation of apparatus, and a control algorithm for use in automatically controlling an air-conditioning system by sensing multiple conditions and responding by actuating the mechanical components of the air-conditioning system to optimize the temperature of the coolant fluid, provide improved zone temperature control, provide status of system components, and provide an alert if there is overheating of a supply side system mechanical component.

Abstract: A method and apparatus are disclosed for managing thermal energy transfer between a mold, die or cavity and a thermal transfer fluid. The thermal energy being exchanged with the mold, die or cavity is calculated in real time as a function of the temperature differential between inlet and outlet fluid temperatures, the volumetric rate of fluid delivery, and known characteristics of the fluid. The rate of thermal energy exchange is controlled by varying the fluid delivery rate in accordance with a desired thermal energy exchange profile.

Abstract: A hot water supply apparatus using a heat medium provides a heat medium circulation path that circulates the heat medium, a heat medium pump that pumps the heat medium into the heat medium circulation path, a heat source that generates heat heating the heat medium, a heat medium heat exchanger that exchanges heat generated by the heat source for the heat medium, a hot water supply heat exchanger that exchanges heat of the heat medium circulating in the heat medium circulation path for clean water, and a control unit that sets the heat medium in the heat medium circulation path in a predetermined temperature and controls the rotating speed of the heat medium pump and the combustion amount of the heat source according to a heat requirement.

Abstract: Monitoring method and system are provided for dynamically determining airflow rate through and heat removal rate of an air-conditioning unit, such as a computer room air-conditioning unit. The method includes: sensing inlet and outlet temperatures of fluid passing through a heat exchanger associated with the air-conditioning unit; sensing air temperature at an air inlet side of the heat exchanger; automatically determining at least one of airflow rate through or heat removal rate of the air-conditioning unit, the automatically determining employing the sensed inlet temperature and outlet temperature of fluid passing through the heat exchanger, and the sensed air temperature at the air inlet side of the heat exchanger; and outputting the determined airflow rate through or heat removal rate of the air-conditioning unit. In one embodiment, the heat exchanger is an auxiliary air-to-air heat exchanger, and in another embodiment, the heat exchanger is the air-to-liquid heat exchanger of the air-conditioner.

Abstract: An apparatus for cooling N heat-producing devices, where AT is an integer no smaller than one, using a cooling fluid that may be supplied at a temperature below the dew-point temperature of ambient air. To avoid condensation on the heat-producing devices, the cold fluid is warmed, upstream of the heat-producing devices, to a temperature T0 that is above the dew-point. The warming is accomplished, in a heat exchanger, by the warm fluid returning from the heat-producing devices. The amount of warming is controlled by periodically measuring T0 as well as the N temperatures downstream of the N heat-producing devices, and sending these N+1 temperature measurements to a control element that implements a control algorithm whose purpose is to achieve a set-point value of T0 by regulating, via N control valves, the flow of fluid to the N heat-producing devices. Also provided is a method for cooling the N heat-pro during devices pursuant to the inventive apparatus by a temperature control over the cooling fluid.

Abstract: An apparatus for use with a process liquid for controlling the temperature of a semiconductor-processing target comprises first and second tanks adapted for holding process liquid, at least one fluid level sensor carried by the first tank for monitoring the amount of process liquid in the first tank, and a valve coupled to one of the at least one fluid level sensor and configured to increases the flow of process liquid from the second tank to the target when the amount of process liquid in the first tank drops to a first predetermined amount. The first tank may include first and second compartments partially separated by a divider with a top whereby process liquid in the first compartment flows over the top of the divider into the second compartment.

Abstract: A vehicle cooling system comprises a vehicle unit, a heat exchanger, a cooling fan, a coolant pump, a three-way valve, and a control unit. The heat exchanger is arranged in the coolant route to selectively receive a coolant from the coolant outlet of the vehicle unit. The cooling fan is arranged to blow cooling air to the heat exchanger. The coolant pump is arranged to circulate the coolant through the coolant route. The three-way valve is arranged to switch the coolant route between a heat exchanger route that passes through the heat exchanger and a bypass route that bypasses the heat exchanger. The control unit is configured to control operation of at least one of the cooling fan, the three-way valve and the coolant pump based on a temperature of the coolant at the heat exchanger and a temperature of the coolant at the coolant outlet of the vehicle unit.

Abstract: A constant temperature liquid circulating device includes a heat absorption tube through which flows heat absorbing liquid, a tank containing a constant temperature circulating liquid and a heat exchange portion of the heat absorption tube, a conduit which circulates the constant temperature circulating liquid in the tank to an external device and a flow regulator. The flow regulator includes an electric proportional valve for controlling a flow amount of heat absorbing liquid in the heat absorption tube, an electromagnetic valve for delivering the heat absorbing liquid to the heat exchange portion, and a controller which regulates the flow of the heat absorbing liquid through the electric proportional valve not to be less than a low flow limit value, and which regulates the flow of heat absorbing liquid through the electromagnetic valve so as to adjust the circulating liquid to a predetermined temperature.

Abstract: An air conditioner is provided. The air conditioner includes a heat exchanger which exchanges heat with air by passing a coolant therethrough; an anti-freeze apparatus which prevents the freeze of water on the surface of the heat exchanger by supplying energy to the heat exchanger; and a heat generation unit which heats the heat exchanger. The air conditioner can minimize the need for a defrost operation and can thus continuously and effectively perform an air conditioning function even when water on the surface of the heat exchanger is frozen.

Abstract: A cooling system for a rack-mount server including at least one blade includes a liquid cooling line, a pump connected to the liquid cooling line, at least one heat exchanger connected to the liquid cooling line, a fan module, a control module connected to the fan module and the pump, a feedback module connected to the control module and comprising a sensor configured to measure a feedback control signal, where the control module is configured to adjust an air flow rate through the fan module or a liquid coolant flow rate through the pump based on the feedback control signal.

Abstract: Monitoring method and system are provided for dynamically determining flow rate of a first fluid and a second fluid through a heat exchanger. The method includes: pre-characterizing the heat exchanger to generate pre-characterized correlation data correlating effectiveness of the heat exchanger to various flow rates of the first and second fluids through the heat exchanger; sensing inlet and outlet temperatures of the first and second fluids through the heat exchanger, when operational; automatically determining flow rates of the first and second fluids through the heat exchanger using the sensed inlet and outlet temperatures of the first and second fluids and the pre-characterized correlation data; and outputting the determined flow rates of the first and second fluids. The automatically determining employs the determined effectiveness of the heat exchanger in interpolating from the pre-characterized correlation data the flow rates of the first and second fluids.

Abstract: A standalone flow rate controller for controlling flow rate of cooling or heating fluid through a heat exchanger by providing a control signal to a flow valve actuator so as to open or close a flow valve in response thereto. A first temperature sensor measures an entry temperature of the cooling or heating fluid flowing into the heat exchanger and a second temperature sensor measures an exit temperature of the cooling or heating fluid flowing out of the heat exchanger. A control unit is responsive to a temperature difference between the entry temperature and the exit temperature for adjusting the control signal so as maintain the temperature difference substantially constant.

Abstract: The present invention is a regulating device configured to regulate a temperature T2 of a first medium in accordance with a target temperature. The regulating device comprises a heat exchanger 16, a control valve 14, temperature sensors 2 and 4, temperature sensors 6 and 8, and a heat quantity control unit 30 and a temperature control unit 50 configured to calculate a target exchange heat quantity in the heat exchanger 16, calculate an exchange heat quantity in the heat exchanger 16, add a signal dependent upon a difference between the target exchange heat quantity and the exchange heat quantity to a signal dependent upon a difference between an output of the temperature sensor 4 and the target temperature, and control the control valve 14 so that a difference between the output of the temperature sensor 4 and the target temperature is reduced.

Abstract: In order to provide a method of operating a solar thermal power plant, in which a heat transfer medium is evaporated endothermally by solar radiation in an evaporator section, wherein the evaporator section comprises a plurality of evaporator branches, among which the heat transfer medium is distributed, in which method non-uniform radiation conditions of the evaporator section may be effectively taken into consideration, it is provided that the mass flow distribution at the evaporator section is controlled, wherein the mass flows are adjusted individually at all or a majority of the evaporator branches and a controlled variable is a variable characterizing a spatial energy rise in a respective evaporator branch in a region of the evaporator branch where the heat transfer medium has not yet evaporated.

Abstract: A device for heating liquids having a base structure and at least one heating element connecting to the base structure wherein at least one non-linear channel structure is arranged between the base structure and the heating element for throughflow of a liquid for heating, and whereas the base structure and the heating element are mutually connected by means of at least one soldered connection. A method is disclosed for heating liquids comprising activating a heating element and guiding a liquid for heating through a channel structure.

Abstract: The invention relates to a system for regulating the temperature of a fuel cell that is cooled by a cooling fluid traveling through the cell, the system including both first control means for measuring the temperature of the cooling fluid and for controlling the flow rate of the controlling fluid as a function of said measured temperature of said cooling fluid, comprising second control means for measuring the flow rate of the cooling fluid and for controlling the temperature of the cooling fluid as a function of a flow rate difference between the command flow rate specified by said first control means and said corresponding measured flow rate of the cooling fluid such that said command temperature specified by the second control means compensates for said flow rate difference.

Abstract: A cooling apparatus (10) for cooling a detector (52), the cooling apparatus including an inner and an outer countercurrent heat exchanger (12 and 14, respectively) for a first and a second gas in a thermally insulating housing (16), the inner countercurrent heat exchanger (12) being arranged within a sublength of the outer countercurrent heat exchanger (14), and the inner countercurrent heat exchanger (12) being spatially separated from the outer countercurrent heat exchanger (14) by an outer sleeve (18). In this apparatus, the outer sleeve (18) has a partition plate (32) between an expansion nozzle (28) for the first gas located at the end of the inner countercurrent heat exchanger (12) and the remaining part of the outer countercurrent heat exchanger (14).

Abstract: A fan motor speed control system for controlling the fan motor speed of an air conditioning system includes a power output circuit including a power triac which is turned on and off by an opto-isolator connected to a pulse generator circuit for varying an AC voltage waveform imposed on the fan motor. The pulse generator circuit is connected to heating and cooling ramp circuits and a minimum speed circuit to provide a variable voltage signal imposed on the pulse generator circuit corresponding to the temperature difference sensed by a return air sensor and a heating or cooling sensor or by separate heating and cooling sensors disposed adjacent respective heating and cooling heat exchangers of the air conditioning system. An adjustable minimum speed circuit and a cutoff circuit are provided to control motor minimum speed or motor shutoff when a predetermined minimum speed is reached to prevent motor bearing failure or overheating.

Abstract: Process and device for controlling the temperature of an outbound secondary flow in a secondary circuit from a heat exchanger by a primary flow in a primary circuit, via a member that regulates the primary flow, influenced by a control unit. The enthalpy difference between inbound and outbound primary flow to and from the heat exchanger and the secondary flow are determined. The flow in the primary circuit is determined, and the parameters are supplied to the control unit for controlling the member, whereby the primary flow is controlled in dependence of the secondary flow, so that power supplied to the heat exchanger substantially equals the sum of the power needed to raise the temperature of the secondary flow from the initial temperature to the desired outbound temperature; the assumed power requirement for compensating for energy stored in the heat exchanger; and the assumed leak power from the heat exchanger.

Abstract: A constant temperature refrigeration system for extensive temperature range application comprising a refrigerator, a low-temperature heat exchanger, a medium-temperature heat exchanger, a high-temperature heat exchanger, a pump, a first solenoid valve, a second solenoid valve, a third solenoid valve, a temperature sensor, a power regulator and a controller, the temperature sensor is utilized for determining the working fluid temperature and compare the actual input temperature, the actual output temperature and the predetermined temperature, and the controller is utilized for controlling the first solenoid valve, the second solenoid valve and the third solenoid valve for conveying the fluid to flow through various heat exchangers so that the working fluid is heated or cooled, with the result being that the working fluid temperature outputted is to reach the predetermined temperature, so as to acquire the working fluid having the exactly and precisely predetermined low temperature (?40° C. to 25° C.

Abstract: A coolant circuit (10) includes at least one heat source (12), a radiator (14), and a bypass line (22), which connects a radiator inlet (18) to a radiator return (20) and whose junction (24) has a control valve (26) disposed on it, whose throttle body (58) can be electrically triggered as a function of operating parameters and environmental parameters by means of at least one control unit (40, 42) and divides the coolant flow between the radiator inlet (18) and the bypass line (22). According to a characteristic curve of the control valve (26), the control unit (40, 42) determines a set-point value (50) for the position of the throttle body (58), which sets a ratio of the radiator volume flow to the total coolant flow at the control valve (26).

Abstract: The absence or shortage of a heat transfer medium can be detected without any time lag. While the medium is circulated through a water jacket and an exhaust gas heat exchanger which receives heat from the exhaust gas, heat generated by the engine can be recovered. A first sensor is provided at a waste heat recovering location in a circulation path of the medium. A second sensor is provided at a downstream side of sensor. When the medium is absent, a difference in measured temperature develops between sensor and sensor. A heat transfer medium shortage signal is outputted when the difference in the measured temperature between the first sensor and the second sensor exceeds a predetermined reference level.

Abstract: A fan motor speed control system for controlling the fan motor speed of an air conditioning system includes a power output circuit including a power triac which is turned on and off by an opto-isolator connected to a pulse generator circuit for varying an AC voltage waveform imposed on the fan motor. The pulse generator circuit is connected to heating and cooling ramp circuits and a minimum speed circuit to provide a variable voltage signal imposed on the pulse generator circuit corresponding to the temperature difference sensed by a return air sensor and a heating or cooling sensor or by separate heating and cooling sensors disposed adjacent respective heating and cooling heat exchangers of the air conditioning system. An adjustable minimum speed circuit and a cutoff circuit are provided to control motor minimum speed or motor shutoff when a predetermined minimum speed is reached to prevent motor bearing failure or overheating.

Abstract: A forced air heating and/or cooling system utilizing an induction type fan motor is controlled by a controller circuit which is operable to continuously vary the speed of the fan motor during a start-up phase and a shut-down phase of the heating and/or cooling cycle. The controller circuit includes terminals for connection to the source of electrical energy for the heating and/or cooling system and for connection to the system controls without altering the control function or circuitry thereof. The controller circuit includes temperature sensors which are operable to control start-up and shutdown of the fan motor over continuously variable speed operating cycles in response to sensed temperature of the air being circulated by the fan.

Abstract: A control system for the room temperature in large area heating systems comprises a feed-line manifold and a return-line manifold and for each heating loop an electrically activated throttle valve. A control-unit automatically adjusts the throttle degree of each heating loop so that the temperature difference between the feed-line temperature and the return-line temperature of each heating loop is the same.

Abstract: The present invention is a new self-balancing modulating control valve for use in a variable-flow fluid distribution system supplying a plurality of loads, which when installed at each load permits a smaller pumping head at all flow conditions. The purpose of this invention is to develop a valve for a variable-flow fluid distribution system that uses less energy than current systems by requiring a near zero pressure drop across the valve but still operates effectively at all load and flow conditions. This invention can allow electronically actuated ball-type valves that are now available to operate reliably and with a longer life by achieving effective control with less frequent reposition requirements.

Abstract: A method and device for controlling the operation of a heat pump having a primary heat system and an auxiliary heat system, and used to heat air circulating in an enclosure such as a building, the invention comprising a first sensor positioned in the return duct of the heating system for measuring the temperature of air being returned to the heat system from the enclosure, a second sensor for measuring the temperature of air which has been heated only by the primary heat system, a temperature comparing relay for comparing the two sensed temperatures and determining the difference between them and actuating the auxiliary heat system only when the temperature difference is less than a predetermined set point, for example 4° F., thereby providing a significantly enhanced operating efficiency of the heating system.

Abstract: A system for controlling the humidity with a residential air conditioning system without compressor or air flow control employs a simple control technique of matching inlet air temperature prior to the refrigeration coils of the air conditioning system to outlet temperature after the refrigeration coil and as raised by a reheat coil supplied with hot water from the residential hot water heater. The system permits heating and cooling cycles and may be retrofit into existing residential units.

Abstract: A heat recovery unit comprising a case (1), which encloses at least one regenerative heat accumulator (5), whereby the casing (1) has a supply air opening (10), an exhaust air opening (15), an exterior air opening (20) and a under-air opening (25), and whereby exhaust air and supply air alternately pass through the heat accumulator (5). The heat accumulator (5) has, via a rotational movement, a valve function which opens and respectively closes the openings (10-25) when the heat accumulator (5) rotates from a first position for exhaust air throughflow to a second position for exterior air throughflow.

Abstract: A combination of setting a correction value of an atmospheric temperature for each temporal section in response to a predicted value of a variation of the atmospheric temperature in a day and a delayed variation of a temperature of hydraulic oil due to thermal inertia and correcting a command value for a temperature regulation of the hydraulic oil at a supply source of the hydraulic oil in response to the correction value of the atmospheric temperature, performing a feed forward compensation of the temperature of the hydraulic oil with respect to the variation of the atmospheric temperature for the day as a cyclic period, permits a working body of hydraulic oil to be kept at an adequate temperature, even under working conditions subjected to significant influences of atmospheric temperature variations and thermal inertia.