A method for determining superheat for an air-conditioning system or a heat pump system using a virtual superheat measurement system. The method includes a obtaining a compressor efficiency; acquiring concurrent noninvasive measurements of a suction, a discharge, and a condensing temperature; determining a discharge pressure as a saturated pressure corresponding to the condensing temperature; determining a first discharge enthalpy and a discharge entropy as functions of the discharge temperature and the calculated discharge pressure; for all possible values of suction pressure: guessing the suction pressure; determining a suction enthalpy and a suction entropy as functions of guessed suction pressure and suction temperature; determining a second discharge enthalpy as a function of the discharge pressure and the calculated suction entropy; and determining a second compressor efficiency as the difference between the second discharge enthalpy and the suction enthalpy divided by the difference between the first discharge enthalpy and the suction enthalpy.

An HVAC system is provided. Embodiments of the present disclosure generally relate to heat exchangers having tubing with a reduced diameter compared to traditional systems. In one embodiment, a ducted HVAC system comprises an outdoor heat exchanger with tubing that has an outer diameter of eight millimeters (8 mm) or less and an indoor heat exchanger with tubing that has an outer diameter of nine millimeters (9 mm) or less. Additional systems, devices, and methods are also disclosed.

An air handling unit (AHU) system is provided and includes an AHU. The AHU includes an enclosure formed to define an inlet and at least one outlet downstream from the inlet, an air supply system to drive an air flow through the enclosure from the inlet to the outlet and a misting system operably coupled to the AHU. The misting system is configured to spray high pressure, cold water mist that includes mist droplets into a portion of the enclosure upstream from the at least one outlet whereupon heat transfer occurs directly between the mist droplets and air prior to the air reaching the outlet.

An air handling unit (AHU) system is provided and includes an AHU. The AHU includes an enclosure formed to define an inlet and at least one outlet downstream from the inlet, an air supply system to drive an air flow through the enclosure from the inlet to the outlet and a misting system operably coupled to the AHU. The misting system is configured to spray high pressure, cold water mist that includes mist droplets into a portion of the enclosure upstream from the at least one outlet whereupon heat transfer occurs directly between the mist droplets and air prior to the air reaching the outlet.

A transfer tube for a thermal transfer device can include at least one wall having an inner surface and an outer surface, where the inner surface forms a cavity, where the at least one wall further has a first end and a second end. The first end can be configured to couple to a terminus of a heat exchanger of the thermal transfer device. The second end can be configured to couple to a collector box of the thermal transfer device. At least a portion of the at least one wall can be disposed in a vestibule of the thermal transfer device. The cavity can be configured to simultaneously receive a first fluid that flows from the first end to the second end and a second fluid that flows from the second end to the first end.

A safety system implemented within a structure includes a source of breathable air, and a fixed piping system to supply the breathable air from the source to each interior region of a number of interior regions across the structure. The fixed piping system is implemented in a ringed architecture including a first portion of the fixed piping system proximate the each interior region and a second portion thereof farther away from the each interior region. In accordance with the ringed architecture, the first portion and the second portion are implemented as a continuous ring with respect to the source of the breathable air such that, even during a compromise of a first sub-portion of the first portion, unaffected by the compromise, the breathable air continues to be supplied to a second sub-portion of the first portion by way of the second portion.

A safety system implemented within a structure includes a source of breathable air, and a fixed piping system to supply the breathable air from the source to each interior region of a number of interior regions across the structure. The fixed piping system is implemented in a ringed architecture including a first portion of the fixed piping system proximate the each interior region and a second portion thereof farther away from the each interior region. In accordance with the ringed architecture, the first portion and the second portion are implemented as a continuous ring with respect to the source of the breathable air such that, even during a compromise of a first sub-portion of the first portion, unaffected by the compromise, the breathable air continues to be supplied to a second sub-portion of the first portion by way of the second portion.

Disclosed herein are an air conditioner system and a controlling method thereof. In a situation that air-conditioning systems such as air conditioners and refrigerators are installed and operated in a site, real-time operation data are acquired and the air conditioning and efficiency are calculated at the site. By comparing performance data provided by a device manufacturer and the real-time operation data, device performance is corrected for the site's installation environment. By using corrected device performance, it is possible to save building facility energy by providing optimal operation number control suitable for the installation environment.

Disclosed herein are an air conditioner system and a controlling method thereof. In a situation that air-conditioning systems such as air conditioners and refrigerators are installed and operated in a site, real-time operation data are acquired and the air conditioning and efficiency are calculated at the site. By comparing performance data provided by a device manufacturer and the real-time operation data, device performance is corrected for the site's installation environment. By using corrected device performance, it is possible to save building facility energy by providing optimal operation number control suitable for the installation environment.

A refrigeration cycle apparatus includes a refrigerant circuit in which a compressor, a first heat exchanger, an expansion mechanism, and a second heat exchanger are connected by pipes. The first heat exchanger includes a first refrigerant passage and a second refrigerant passage that share a plurality of fins with each other and provided in parallel in the refrigerant circuit. The apparatus further includes a high-and-low-pressure switching mechanism which is located on an inlet side of the second refrigerant passage of the first heat exchanger in flowing of refrigerant in an operation in which the first heat exchanger functions as a condenser, and which performs switching between flow directions of the refrigerant. The apparatus further includes a refrigerant blocking mechanism located on an outlet side of the second refrigerant passage of the first heat exchanger in the flowing of the refrigerant in the operation, and which blocks the flowing of the refrigerant.