Abstract: A dedicated outside air-conditioning system (DOAS) that may automatically generate variable subcooling refrigerant delivered to the evaporator; and modulate hot discharge gas to reduce the relative humidity of the discharge air from the DOAS. The DOAS may include fluid control valves configured to regulate delivery of the refrigerant in order to seamlessly flex between maximum latent capacity (minimum discharge dewpoint) and maximum sensible capacity (minimum leaving air discharge dry bulb temperature) to match load and/or ventilation air requirements.

Abstract: An improved heat pump apparatus configured to transfer heat by circulating a refrigerant through a cycle of evaporation and condensation without the need to run a defrost cycle—the No-Frost Heat Pump (NFHP)—is provided. The NFHP is configured with a four-way valve, a suction accumulator, and a compressor to pump and exchange a refrigerant between two heat exchange coil/coils—an outdoor heat exchange coil/coil (also known as the source coil) and an indoor heat exchange coil/coil (also known as the load coil)—in order to exchange heat between the indoor/outdoor heat exchange coils. The NFHP is further configured with a means for controlling hot gas discharge—the means comprising a discharge valve or a discharge gas injection valve configured to inject refrigerant into the outdoor heat exchange coil inlet/source coil, thereby preventing the formation of ice/frost on the surface of the coil while operating in heating mode at low outdoor ambient temperatures.

Abstract: A dedicated outside air system comprising a combined variable refrigerant flow and variable air flow that provides ventilation in an energy efficient way or otherwise as desired.

Abstract: A dedicated outside air system comprising a combined variable refrigerant flow and variable air flow that provides ventilation in an energy efficient way or otherwise as desired.