Application of ASHRAE Standard 15-2010 with Respect to Multi-Evaporator Split Air-Conditioning Systems

摘要

Multi-evaporator split air-conditioning systems, especially Variable Refrigerant Flow (VRF) systems, are receiving increased attention in the marketplace, as an alternative to water-source heat pump loops, hydronic fan-coil networks, room-by-room packaged terminal units, and even all-air systems. These systems are sometimes characterized by a significant amount of field refrigerant piping, a large number of evaporators on a common refrigerant pipe network with one condensing unit, and safety concerns related to the potential for refrigerant leaks. This paper examines the consequences and safety-based limitations imposed on such systems by ANSI/ASHRAE Standard 15-2010, explores some ambiguity not specifically covered by the Standard, attempts to assist the system design engineer on proper application of the Standard, and identifies areas where further study or research is needed to provide sound guidance on the safe application of these systems.