Unlike synthetic refrigerants, ammonia and standard mineral oils do not mix (they are immiscible). Oil is heavier than ammonia and settles at the bottom of vessels and low points in the piping. The handbook outlines: Design of oil separators at the compressor discharge. Installation of oil drop legs and collection points. Safe procedures for draining oil from a live system. Insulation and Vapor Retarders
Ammonia has a high coefficient of thermal expansion. If liquid ammonia is trapped between two closed valves (e.g., during maintenance or a power outage), ambient heat will cause the pressure to rise rapidly, leading to a catastrophic pipe rupture. The handbook mandates the installation of hydrostatic relief valves wherever liquid trapping can occur, venting the excess pressure back to a lower-pressure part of the system or to a safe atmosphere. Minimizing Mechanical Joints Iiar Ammonia Refrigeration Piping Handbook Pdf
Liquid feed lines (recirculated, flooded, and direct expansion) High-pressure receiver piping Oil Management and Return Installation of oil drop legs and collection points
IIAR Ammonia Refrigeration Piping Handbook is an essential technical reference published by the International Institute of Ammonia Refrigeration (IIAR) If liquid ammonia is trapped between two closed valves (e
Features high-pressure discharge lines, oil separation systems, and complex manifold piping. Designs must prioritize vibration dampening and clear maintenance access.
All welding must comply with Section IX of the ASME Boiler and Pressure Vessel Code. Welders must be certified for the specific procedures used.
The International Institute of Ammonia Refrigeration (IIAR) Ammonia Refrigeration Piping Handbook is the definitive guide for designing, installing, and maintaining safe industrial refrigeration systems. Ammonia ( NH3cap N cap H sub 3