Abstract: The present application concerns a climate control unit for controlling air temperature and/or humidity. Moreover, the present application concerns a system comprising such a climate control unit. The climate control unit according to the invention makes use of two refrigerant paths that share a common part in which a compressor and evaporator are arranged, and that each have a non-shared part. A reheat coil is provided in one of the non-shared parts. According to the invention, a respective expansion device is provided in both non-shared parts.

Abstract: A modulating refrigeration system includes an evaporation unit and a condensing unit. The evaporation unit generates a first output airflow comprising a lower temperature, a lower relative humidity, or both than a first supply airflow and directs the first output airflow into a building. The condensing unit generates a second output airflow at a higher temperature than a second supply airflow and discharges the second output airflow to an unconditioned space. The evaporation unit comprises a first valve operable to direct a portion of refrigerant to a secondary evaporator and primary evaporator or to direct the entire flow of refrigerant to the primary evaporator and bypassing the secondary evaporator.

Abstract: In an embodiment, a method of preventing evaporator coil freeze in a heating, ventilation and air conditioning (HVAC) system is performed by a controller in the HVAC system. The method includes determining a reference saturated suction temperature (SST) via a sensor disposed in relation to an evaporator coil in the HVAC system. The method also includes determining whether the reference SST is below a minimum SST threshold. The method also includes, responsive to a determination that the reference SST is below the minimum SST threshold, increasing a discharge air temperature (DAT) setpoint.

Abstract: A dehumidification system includes a compressor, a primary evaporator, a primary condenser, a secondary evaporator, a secondary condenser, a modulating valve, and an alternate condenser. The secondary evaporator receives an inlet airflow and outputs a first airflow to the primary evaporator. The primary evaporator receives the first airflow and outputs a second airflow to the secondary condenser. The secondary condenser receives the second airflow and outputs a third airflow to the primary condenser. The primary condenser receives the third airflow and outputs a dehumidified airflow. The compressor receives a flow of refrigerant from the primary evaporator and provides the flow of refrigerant to the modulating valve. The modulating valve directs the flow of refrigerant to the primary condenser and to the alternate condenser. The alternate condenser receives a portion of the flow of refrigerant for heat rejection, where the primary condenser receives the remaining portion of the flow of refrigerant.

Abstract: A dehumidification system includes a compressor, a primary evaporator, a primary condenser, a secondary evaporator, and a secondary condenser. The secondary evaporator receives an inlet airflow and outputs a first airflow to the primary evaporator. The primary evaporator receives the first airflow and outputs a second airflow to the secondary condenser. The secondary condenser receives the second airflow and outputs a third airflow to the primary condenser. The primary condenser receives the third airflow and outputs a dehumidified airflow. The compressor receives a flow of refrigerant from the primary evaporator and provides the flow of refrigerant to the primary condenser.

Abstract: A dehumidification system includes a compressor, a primary evaporator, a primary condenser, a secondary evaporator, a secondary condenser, and a water pump. The secondary evaporator receives an inlet airflow and outputs a first airflow to the primary evaporator. The primary evaporator receives the first airflow and outputs a second airflow to the secondary condenser. The secondary condenser receives the second airflow and outputs a dehumidified airflow. The compressor receives a flow of refrigerant from the primary evaporator and provides the flow of refrigerant to the primary condenser. The primary condenser receives the flow of refrigerant and outputs the flow of refrigerant at a lower temperature through heat transfer with a flow of fluid. The flow of fluid is directed, by the water pump, to a heat exchanger or an external source, where heat is rejected from the flow of fluid.

Abstract: A device for exchange of water molecule and temperature between two fluids. The device comprises thin molecular sieve membrane sheets that allow water molecules to permeate through while blocking cross-over of the exchanging fluids. The device provides two sets of flow channels having a hydraulic diameter ranged from 0.5 to 2.0 mm for respective process and sweep fluid flows. The two sets of the channels are separated by a membrane sheet having a thickness less than 200 ?m. The thin molecule sieve membrane may be prepared by forming an ultra-thin zeolite membrane layer on a porous metal-based support sheet which provides very high water permeance so that the exchange can be conducted in a compact membrane module at high throughput. The device can be used to remove water from a process stream of higher water content by use of a sweep fluid of lower water content or higher water affinity.

Abstract: A dehumidification system includes a compressor, a primary evaporator, a primary condenser, a secondary evaporator, and a secondary condenser. The secondary evaporator receives an inlet airflow and outputs a first airflow to the primary evaporator. The primary evaporator receives the first airflow and outputs a second airflow to the secondary condenser. The secondary condenser receives the second airflow and outputs a third airflow to the primary condenser. The primary condenser receives the third airflow and outputs a dehumidified airflow. The compressor receives a flow of refrigerant from the primary evaporator and provides the flow of refrigerant to the primary condenser.

Abstract: An HVAC actuator (1) comprises a motor (12), a motor controller (13) coupled to the motor (12), and a heating apparatus (14) thermally coupled to the HVAC actuator (1). The HVAC actuator (1) further comprises a condensation controller (15) coupled to the heating apparatus (14). The condensation controller (15) is configured to monitor at least one condensation parameter, and to control the heating apparatus (14) using the at least one condensation parameter.

Abstract: An air handling system is disclosed that includes an integral chilled water refrigeration system. The air handling system additionally includes a first coil section that provides cooling and a second coil section that provides heating. The second coil section and associated terminal units are in fluid communication with the first refrigeration system.

Abstract: Included is an indoor device including inside a casing an electrical-component box having electrical components accommodated therein, an indoor-device heat exchanger, and an indoor-device fan to deliver air to the indoor-device heat exchanger. An air conditioner includes a temperature measurement unit to measure a temperature of the indoor-device heat exchanger, and a control unit to determine an upper limit of a rotational speed of the indoor-device fan on the basis of a temperature of the indoor-device heat exchanger measured by the temperature measurement unit, and to execute control to operate the indoor-device fan at a rotational speed equal to or slower than the determined upper limit.

Abstract: A heat exchanger in which a refrigerant and air flow exchange heat includes a first heat-exchanging unit. The first heat-exchanging unit includes: a first header including a first gas refrigerant inlet/outlet; a second header including a first liquid refrigerant inlet/outlet; a plurality of first flat tubes disposed side by side in a longitudinal direction of the first header and the second header; and a first communication path formation portion that is connected to the first header and the second header and that forms a first communication path.

Abstract: A method for conditioning air, the method comprising flowing a first air flow within a first ventilation system past a first cooling coil, which is connected to a cooling system with a cooling fluid and a cooler, characterised in that the temperature of the first air flow, when passing the first cooling coil, is lower than the temperature of the cooling fluid flowing through the first cooling coil and that the first air flow is heated and the cooling fluid flowing through the first cooling coil is cooled, when the first air flow passes through the first cooling coil.

Abstract: Methods and apparatus for latent heat extraction of an air stream eliminates the need for recirculation pumps and uses the pressure in the chilled water supply to the primary chilled water cooling coil to motivate the water through the precooling and reheat coils of a run-around system. The energy transfer lowers the air temperature entering the primary coil so that the primary coil can provide a greater amount of latent heat extraction from the air stream. Both the precooling and the primary coils can share the primary cooling function for periods of peak cooling demand when precooling is not required thereby reducing the required primary cooling coil size. Enhancements combine the function of the precooling coil and the primary cooling coil into a single coil which is specially circuited for installation in the space of a standard chilled water coil eliminating the need for larger equipment rooms.

Abstract: A dehumidification system includes a compressor, a primary evaporator, a primary condenser, a secondary evaporator, and a secondary condenser. The secondary evaporator receives an inlet airflow and outputs a first airflow to the primary evaporator. The primary evaporator receives the first airflow and outputs a second airflow to the secondary condenser. The secondary condenser receives the second airflow and outputs a third airflow to the primary condenser. The primary condenser receives the third airflow and outputs a dehumidified airflow. The compressor receives a flow of refrigerant from the primary evaporator and provides the flow of refrigerant to the primary condenser.

Abstract: Various embodiments of a heat pump system are disclosed to provide improved and flexible heat pump operation when dehumidification of the conditioned space is required. In one embodiment, a heat pump system includes a heat pump loop comprising a refrigerant circuit that fluidly interconnects (1) a compressor; (2) a source heat exchanger; (3) a source heat exchanger bypass circuit comprising a bypass valve; (4) a space heat exchanger; (5) a reversing valve positioned on the discharge side of the compressor; (6) a reheat circuit comprising a reheat heat exchanger; (7) first and second expansion devices; and (8) first and second expansion device bypass circuits configured to allow refrigerant to bypass the first and second expansion devices, respectively, where the first and second bypass circuits include first and second check valves, respectively; and (9) a 3-way valve configured to selectively direct refrigerant flow to the first expansion device, the reheat circuit, and the second expansion device.

Abstract: Methods and apparatus for latent heat extraction of an air stream eliminates the need for recirculation pumps and uses the pressure in the chilled water supply to the primary chilled water cooling coil to motivate the water through the precooling and reheat coils of a run-around system. The energy transfer lowers the air temperature entering the primary coil so that the primary coil can provide a greater amount of latent heat extraction from the air stream. Both the precooling and the primary coils can share the primary cooling function for periods of peak cooling demand when precooling is not required thereby reducing the required primary cooling coil size. Enhancements combine the function of the precooling coil and the primary cooling coil into a single coil which is specially circuited for installation in the space of a standard chilled water coil eliminating the need for larger equipment rooms.

Abstract: Methods and apparatus for latent heat extraction of an air stream eliminates the need for recirculation pumps and uses the pressure in the chilled water supply to the primary chilled water cooling coil to motivate the water through the precooling and reheat coils of a run-around system. The energy transfer lowers the air temperature entering the primary coil so that the primary coil can provide a greater amount of latent heat extraction from the air stream. Both the precooling and the primary coils can share the primary cooling function for periods of peak cooling demand when precooling is not required thereby reducing the required primary cooling coil size. Enhancements combine the function of the precooling coil and the primary cooling coil into a single coil which is specially circuited for installation in the space of a standard chilled water coil eliminating the need for larger equipment rooms.

Abstract: A refrigerated drying module includes a storage cabinet for storing moisture sensitive devices, an air flow loop configured to circulate air into and out of the storage cabinet and a refrigerant loop configured to remove moisture from the air circulated through the air flow loop. The refrigerated drying module is configured to remove moisture from air drawn from the storage cabinet and collect the removed moisture as ice formed on the surface of an evaporator coil included in the refrigerant loop.

Abstract: In various implementations, a request for operation of an air conditioner may be received. The air conditioner may include a cooling mode and/or a dehumidifying mode. In some implementations, a compressor speed for a compressor of the air conditioner may be determined, and which mode(s) of the air conditioner to allow may be determined based at least partially on the determined compressor speed.

Abstract: An outdoor heat exchanger includes a fan configured to adjust a heat transfer coefficient ao of the outside of a heat transfer tube through which a refrigerant flows, a bypass passage and flow rate control valve configured to adjust a heat transfer coefficient ?i of the inside of the heat transfer tube through which the refrigerant flows, and an on-off valve configured to adjust a heat transfer area A where the refrigerant exchanges heat with a heat medium. A controller controls the heat transfer coefficient ?o of the outside of the heat transfer tube, the heat transfer coefficient ?i of the inside thereof, and the heat transfer area A to control a heat exchange amount of the outdoor heat exchanger.

Abstract: In various implementations, a request for operation of an air conditioner may be received. The air conditioner may include a cooling mode and/or a dehumidifying mode. In some implementations, a compressor speed for a compressor of the air conditioner may be determined, and which mode(s) of the air conditioner to allow may be determined based at least partially on the determined compressor speed.

Abstract: A water production system with a thermal separation device that defines a cold region and a hot region, a fluid-air heat exchanger located remotely from the thermal separation device and exposed to air, and a fluid circulation loop that thermally connects the cold region of the thermal separation device to the fluid-air heat exchanger so as to cool the fluid-air heat exchanger and condense water from ambient air to produce water pure enough so that with further treatment it can be made potable. Also disclosed are filtration and dispensing features that are appropriate for a potable water supply.

Abstract: A container refrigeration device aims to prevent low temperature damage to freight in a container. The container refrigeration device includes: a temperature controlling section (101) configured to perform, in a switchable manner, first temperature control under which a temperature inside the container (C) is controlled based on a blown air temperature (Tss) and second temperature control under which the temperature inside the container (C) is controlled based on a suction air temperature (Trs) during dehumidification operation; and a control switching section (103) configured to switch the first temperature control to the second temperature control when the blown air temperature (Tss) is higher than the suction air temperature (Trs) during the dehumidification operation in which part of a refrigerant discharged from a compressor (30) is allowed to flow into a reheat heat exchanger (83).

Abstract: A vehicle heat pump air-conditioning system is provided, which is capable of securing a temperature linearity characteristic during dehumidifying heating, slowing progression of a frost formation on an exterior evaporator during heating, and stably continuing a heating operation while suppressing variations in a blowout temperature. In a cooling refrigeration cycle (14) becoming a base, an interior condenser (8) disposed in a HVAC unit (2) is connected to an exterior condenser (10) in parallel via switching means (15), an exterior evaporator (17) is connected to first decompression means (12) and an interior evaporator (7) in parallel via second decompression means (16), a heating heat pump cycle (18) is configured, the first decompression means (12) and the second decompression means (16) are on-off valve function attached decompression means (12, 16), and the exterior evaporator (17) and the interior evaporator (7) can be simultaneously used during dehumidifying heating and heating.

Abstract: An air-conditioner that conditions air inside a passenger compartment of a vehicle using a heat pump refrigerating cycle includes: a case having at least a first air passage and a second air passage independent from each other; an indoor heat exchanger cooling air; and a heating heat exchanger heating air. Inside of the heating heat exchanger is divided into a first section corresponding to the first air passage and a second section corresponding to the second air passage. The first section and the second section are located adjacent with each other through a border portion. The heating heat exchanger has a refrigerant passage through which refrigerant flows in parallel with the border portion.

Abstract: A conditioning system that conditions exterior air for use in a spray booth. The exterior air is conditioned and subsequently used to carry away coating mist, dust, and contaminants from a spray area. The conditioning system heats, cools, humidifies, and dehumidifies the exterior air to a variable set point. The variable set point, while bounded by dry-bulb temperature and relative humidity constraints, is selected based upon cost and/or energy minimization. Additionally, the set point selection may be based upon future predicted weather conditions that are determined with a mathematical profile of previous weather conditions and weather trends in a localized domain, where the localized domain is a geographic area surrounding a manufacturing plant that includes a spray booth.

Abstract: An air dehumidifier, and a method for dehumidifying, for a frequency converter arrangement including a surface to be cooled, on which humidity condenses when the surface is being cooled and when, at the same time, the inside of the frequency converter cabinet is possibly being heated. The air dehumidifier is positioned inside the frequency converter cabinet and including at least one air/liquid heat exchanger.

Abstract: A vehicle air-conditioning system (1) includes an HVAC unit (2) in which a first refrigerant evaporator (6) and a second refrigerant condenser (7) are disposed in an air channel (5) communicating with a vehicle interior space; and a heat pump cycle (3) in which a refrigerant compressor (8), a refrigerant switching device (9), a first refrigerant condenser (10) that exchanges heat with the outside air, a first expansion valve (13), and a first refrigerant evaporator (6) are connected in sequence and in which the second refrigerant condenser (7) is connected in parallel with the first refrigerant condenser (10) via the refrigerant switching device (9). An exhaust-heat recovery circuit (21) equipped with a second refrigerant evaporator (16) disposed in a ventilation channel (17) from the vehicle interior and a second expansion valve (15) is connected in parallel with the first expansion valve (13) and the first refrigerant evaporator (6) of the heat pump cycle (3).

Abstract: A system for regulating the amount of outdoor air that is introduced into a building determines characteristics of the outdoor air using sensor inputs. The system uses extremum seeking control logic to vary the flow of outdoor air provided into the building in response to the cooling load determinations.

Abstract: An HVAC system including a compressor, a condenser and an evaporator arrangement connected in a closed refrigerant loop. The evaporator arrangement includes a plurality of refrigerant circuits. The evaporator arrangement also includes at least one distributor configured to distribute and deliver refrigerant to each circuit of the plurality of circuits. The plurality of circuits are arranged into a first and second set of circuits. The evaporator arrangement also includes a valve configured and disposed to isolate the first set of circuits from refrigerant flow from the condenser and provide flow of refrigerant from the compressor in a dehumidification operation of the HVAC system.

Abstract: An air control apparatus having a refrigerant compressor, a condenser, an evaporator coil, and a reheat coil associated with a four way valve to selectively regulate flow of refrigerant to and from the condenser, evaporator coil and reheat coil to control the temperature and humidity of an enclosed environment.

Abstract: A system for controlling temperature and humidity in an enclosure, that has a central air conditioning system; a dehumidifier attached to a return air duct of the central air conditioning system; and a system control unit that comprises a thermostat, dehumidstat and can control a cooling solenoid valve to provide temperature control, and control a dehumidifier solenoid valve to provide humidity control. The cooling solenoid valve and the dehumidifier solenoid valve can be independently activated based on the temperature and humidity of the enclosure. Embodiments of the present invention include systems that are easily modify existing air conditioning systems.

Abstract: A humidity control method is provided for a multi-stage cooling system having two or more refrigerant circuits that balances humidity control and cooling demand. Each refrigerant circuit includes a compressor, a condenser and an evaporator. A hot gas reheat circuit having a hot gas reheat coil is connected to one of the refrigerant circuits and is placed in fluid communication with the output airflow from the evaporator of that refrigerant circuit to provide additional dehumidification to the air when humidity control is requested. The hot gas reheat circuit bypasses the condenser of the refrigerant circuit during humidity control. Humidity control is only performed during cooling operations and ventilation operations.

Abstract: The system and method for increasing efficiency of heat pumps employs temperature sensors to measure the indoor refrigerant coil (indoor heat exchanger) and supply duct air temperature in a heat pump system to vary the indoor air flow rate based on the amount of heat being supplied by the heat pump. By monitoring the indoor refrigerant coil temperature, and the supply duct air temperature near the unit, the airflow can be adjusted to match the BTU (heat) output of the heat pump system. Less air flow over a cooler indoor refrigerant coil temperature allows increased, more efficient, heat transfer, allowing the cooler indoor refrigerant coil temperature to more effectively warm the air. Additionally, with airflow reduced when the indoor refrigerant coil is operating at lower than optimal temperatures or during a defrost cycle, the reduced airflow into living spaces presents a less drafty and more comfortable condition.

Abstract: A system dehumidifies a non-environmentally controlled, enclosed space of a building, for example a crawlspace, using a dehumidifier unit comprising an evaporator coil, a condenser coil, and a compressor arranged for circulating heat exchanger fluid through the coils. A fan operates in series with closed loop ducting to communicate air from the space to the dehumidifier unit and back to the space independently of an HVAC system of the building. The fan and dehumidifier unit are responsive to a dehumidistat. A distributed outlet distributes air from the unit to peripheral positions about the space. A heater is coupled in series with the ducting for heating air circulated therethrough.

Abstract: Multi-circuit refrigerant systems are provided with better control over a dehumidification function. In one embodiment, system circuits have means of communication with each other through connecting lines and flow control devices operable on demand. In another embodiment, a single reheat heat exchanger is utilized for both circuits, ensuring heat transfer interaction between the circuits. In yet another embodiment, a control unit operates refrigerant circuits in such a way that if some circuits are in a reheat mode, the remaining circuits are either shut off or are in an enhanced reheat mode.

Abstract: A system and humidity control method is provided for a multi-stage cooling system having two or more refrigerant circuits that balances humidity control and cooling demand. Each refrigerant circuit includes a compressor, a condenser and an evaporator. A hot gas reheat circuit having a hot gas reheat coil is connected to one of the refrigerant circuits and is placed in fluid communication with the output airflow from the evaporator of that refrigerant circuit to provide additional dehumidification to the air when humidity control is requested. The hot gas reheat circuit bypasses the condenser of the refrigerant circuit during humidity control. Humidity control is performed during cooling operations and ventilation operations. During a first stage cooling operation using only one refrigerant circuit and having a low cooling demand, the request for humidity control activates the hot gas reheat circuit for dehumidification and activates a second refrigerant circuit to provide cooling capacity.

Abstract: A humidistat including an air inlet defining a beginning of an airflow path through the humidistat, a humidity sensor for enabling measurement of the humidity of air flowing along the airflow path, a baffle, a heat source for heating air along a portion of the airflow path, the baffle and the heat source cooperating to define two zones in the humidistat, and an air outlet defining an end of the airflow path. During operation of the humidistat, the air temperature is higher in one zone than in the other zone, and the higher air temperature zone is downstream from the lower air temperature zone in the airflow path.

Abstract: A vapor compression air conditioning system, including a heat pump embodiment, provides enhanced dehumidification of supply air to an enclosed space. The refrigerant fluid circuit includes an evaporator and a reheat heat exchanger for controlling temperature and dehumidification of supply air. A variable speed fan motor controls air flow over an outdoor condenser heat exchanger whereby condenser heat exchange may be shifted progressively between the reheat heat exchanger and the condenser heat exchanger. One alternate embodiment includes a thermosiphon system for heat transfer to and from the reheat heat exchanger. Another embodiment includes a bypass air flow control damper for controlling flow of supply air through the evaporator and the reheat heat exchanger.

Abstract: The invention concerns a method using a system (10) for heating or cooling air in a motor vehicle passenger compartment provided with a windscreen, by input into the passenger compartment air which has passed through an exchanger (12) comprised in a refrigerant loop. The invention is characterized in that it comprises steps which consist in measuring the temperature of the air leaving the exchanger (12), measuring the humidity of the air leaving the exchanger (12), determining the dew point of the air leaving the exchanger (12) based on said temperature and humidity, determining the windscreen temperature, comparing the dew point with the windscreen temperature and stopping the heating of air in the passenger compartment when the dew point is higher than the windscreen temperature.

Abstract: The present invention is a confined space conditioning system, which is used to provide conditioning to localized zones of an enclosure. The confined space conditioning system consists of a conditioning unit and an enveloped space, enveloping the localized zone, connected to the conditioning unit. The conditioning unit uses a low wattage compressor and a heater element to generate cool, dehumidified air or warm conditioned air to the enveloped space, as is required by a user of the system. The used conditioned air is extracted from the enveloped space and is recirculated to the conditioning unit for reconditioning. The surfaces of the enveloped space are thermally insulated using thermally insulating media in order to minimize the cross flow of heat.

Abstract: A temperature control output branch unit D_MV_Temp outputs a manipulated variable to a heating actuator Act1 when the manipulated variable output MVT of a temperature controller PID_Temp is in a heating mode, and outputs it to a cooling actuator Act2 when the output MVT is in a cooling mode. A humidity control output branch unit D_MV_Hum outputs a manipulated variable to a humidifying actuator Act3 when the manipulated variable output MVH of a humidity controller PID_Hum is in a humidifying mode, and outputs it to the actuator Act2 when the output MVH is in a dehumidifying mode. A cooling output maximum value operation unit C_MAX gives whichever is larger of respective manipulated variable outputs from the branch units D_MV_Temp and D_MV_Hum to the actuator Act2.

Abstract: The present invention is a confined space conditioning system, which is used to provide conditioning to localized zones of an enclosure. The confined space conditioning system consists of a conditioning unit and an enveloped space, enveloping the localized zone, connected to the conditioning unit. The conditioning unit uses a low wattage compressor and a heater element to generate cool, dehumidified air or warm conditioned air to the enveloped space, as is required by a user of the system. The used conditioned air is extracted from the enveloped space and is recirculated to the conditioning unit for reconditioning. The surfaces of the enveloped space are thermally insulated using thermally insulating media in order to minimize the cross flow of heat.

Abstract: In accordance with the present invention, a space conditioning system having multi-stage cooling and dehumidification capability is provided. The system includes plural refrigeration circuits operable in a cooling mode to provide cooled air to an indoor space. At least one of the refrigeration circuits is also operable in a reheat mode, wherein air is dehumidified by cooling it and then reheating it before it is supplied to the space. A control system is provided for controlling the operation of the refrigeration circuits to satisfy both a demand for cooling and a demand for dehumidification. Depending upon the level of demand for cooling, the system is operated to satisfy the dehumidification demand and the cooling demand simultaneously. However, in response to a higher level of demand for cooling (e.g., a second stage demand, or in some cases, a higher demand), the demand for cooling takes priority over the dehumidification demand.

Abstract: An improved vehicle climate control system develops a fog factor indicative of the relative potential of windglass fogging, and uses the index to schedule offsets to normal control settings of the system. The air dewpoint temperature at the front windglass is estimated based on relative humidity and a reference temperature, and the fog factor is determined as a function of the estimated air dewpoint temperature and a measure of the windglass temperature. The fog factor is used to offset an air inlet door, mode doors, refrigerant compressor capacity, discharge air temperature, and blower motor speed.