An air conditioner unit includes a housing with an outdoor heat exchanger assembly and an indoor heat exchanger assembly therein. A makeup air intake duct an a makeup are exhaust duct are disposed above the housing parallel to each other. The air conditioner unit also includes a heat exchanger having a first coil and a second coil. The first coil is disposed within the makeup air intake duct. The second coil is disposed with the makeup air exhaust duct. The heat exchanger also includes a first pipe connecting an outlet of the first coil to an inlet of the second coil and a second pipe connecting an outlet of the second coil to an inlet of the first coil.

A heat pipe heat exchanger is used in combination with a damper assembly to selectively control an amount of heat exchange provided. A divider defines discrete heat pipe plenums and bypass plenums within a duct, and the heat pipe system is configured so that all of the coils of one portion of the heat pipe system are received in the heat pipe plenum(s), while the bypass plenum(s) are free of any coils. The damper assembly includes adjustable heat pipe dampers aligned with the heat pipe plenums and adjustable bypass dampers aligned with the bypass plenums.

A heat pipe system including a heat pipe having a first end and a second end for transferring working fluid from the first to the second end, a first reservoir in fluid communication with the first end for holding working fluid in liquid form, a first heat exchanger for transmitting thermal energy from a heat source to working fluid in the first reservoir to vaporize the fluid, a second heat exchanger for transmitting thermal energy from vaporized working fluid to a heat sink thereby condensing the fluid, a return conduit and a pump for pumping the condensed working fluid along the return conduit, where the heat pipe, the return conduit and the first reservoir form a hermetically sealed circuit. A method of transferring thermal energy using a heat pipe system is also disclosed.

An air conditioner unit includes a housing with an outdoor heat exchanger assembly and an indoor heat exchanger assembly therein. A makeup air intake duct an a makeup are exhaust duct are disposed above the housing parallel to each other. The air conditioner unit also includes a heat exchanger having a first coil and a second coil. The first coil is disposed within the makeup air intake duct. The second coil is disposed with the makeup air exhaust duct. The heat exchanger also includes a first pipe connecting an outlet of the first coil to an inlet of the second coil and a second pipe connecting an outlet of the second coil to an inlet of the first coil.

A dehumidifying system includes an enclosure having at least one opening disposed at a first end and at least one opening disposed at a second end. A plurality of air paths that extend through the enclosure and are separated from one another by partitions along at least a portion of the enclosure. A dehumidifier evaporator is disposed within the enclosure and configured such that at least one of the air paths is disposed to flow through the dehumidifier evaporator. The dehumidifier evaporator includes a dehumidifying coil and a heat pipe assembly at least partially wrapping around the dehumidification coil.

Systems and methods for controlling conditions in an enclosed space, such as a data center, or for providing cooling to a device, can include using a Liquid-to-Air Membrane Energy Exchanger (LAMEE) as an evaporative cooler. The LAMEE or exchanger can cool water to the outdoor air wet bulb temperature in a cooling system disposed outside of the enclosed space or device. The reduced-temperature water can be delivered to the enclosed space or device or can cool a coolant that is delivered to the enclosed space or device. The air in the enclosed space, or one or more components in the enclosed space, can be cooled by delivering the reduced-temperature water or coolant to the enclosed space, rather than moving the supply air from the enclosed space to the cooling system. In an example, the cooling system can include one or more cooling coils, upstream or downstream of the LAMEE.

An air-conditioning apparatus using a heat pipe is provided, where the state of the outside air is compared with the state of set supply air. The heat exchange and mixed supply of outside air and ventilation air are effectively performed by changing the passage of the ventilation air and the outside air through the selective opening/shutting of dampers, cooling the outside air through latent heat by spraying mist, and by controlling supply air in a set state through the cooling and humidification of the supply air. Accordingly, energy efficiency can be improved and the energy necessary for the air-conditioning apparatus can be reduced using the evaporation latent heat of water. Furthermore, operation costs can be reduced and financial gains can be obtained because an efficient operation can be performed in response to the state of a measured outside air.

Systems and methods for controlling conditions in an enclosed space, such as a data center, or for providing cooling to a device, can include using a Liquid-to-Air Membrane Energy Exchanger (LAMEE) as an evaporative cooler. The LAMEE or exchanger can cool water to the outdoor air wet bulb temperature in a cooling system disposed outside of the enclosed space or device. The reduced-temperature water can be delivered to the enclosed space or device or can cool a coolant that is delivered to the enclosed space or device. The air in the enclosed space, or one or more components in the enclosed space, can be cooled by delivering the reduced-temperature water or coolant to the enclosed space, rather than moving the supply air from the enclosed space to the cooling system. In an example, the cooling system can include one or more cooling coils, upstream or downstream of the LAMEE.

A heat exchanger for exchanging heat between first and second duct portions of a ventilation system includes first and second heat pipe portions in the first and second duct portions, respectively. Each heat pipe portion can be a heat pipe subassembly including one or more vertical heat pipes fluidly coupled to top and bottom headers, which are respectively connected to the top and bottom headers of the other subassembly to form a refrigerant loop. One or more flow restrictors can block air flow through a respective section of the first or second duct portion. The blocked section can be operatively aligned with a segment of the respective heat pipe portion along which there is a low probability of refrigerant phase change. Each flow restrictor can be an adjustable damper. The damper(s) can be selectively opened and closed as the ventilation system switches between heating and cooling modes.

A heat exchanger for exchanging heat between first and second duct portions of a ventilation system includes first and second heat pipe portions in the first and second duct portions, respectively. Each heat pipe portion can be a heat pipe subassembly including one or more vertical heat pipes fluidly coupled to top and bottom headers, which are respectively connected to the top and bottom headers of the other subassembly to form a refrigerant loop. One or more flow restrictors can block air flow through a respective section of the first or second duct portion. The blocked section can be operatively aligned with a segment of the respective heat pipe portion along which there is a low probability of refrigerant phase change. Each flow restrictor can be an adjustable damper. The damper(s) can be selectively opened and closed as the ventilation system switches between heating and cooling modes.