General. This military handbook covers only direct
expansion systems for HVAC systems. There is an entire ASHRAE
Handbook devoted to food and industrial refrigeration.
Refrigerant piping is slightly different from other piping
because refrigerant gas is difficult to contain, so that special
fittings (wrought copper or forged brass) and high melting point
solder (1,000 degrees F) are needed to achieve a tight system,
and provision must be made to ensure oil return to the
Sizing. See the ASHRAE Handbook, Refrigeration for
flow rate charts on sizing the liquid, suction, and hot gas lines
with various refrigerants.
See Figures 31 and 32 for refrigerant