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Interpretation IC 15-1989-1 – March 20, 1990 (Ref. requirements for low-side pressure relief on packaged chillers, especially whether pressure relief is required when a shell-and-tube, direct-expansion heat exchanger is used on the low pressure side)
Interpretation IC 15-1989-2 – August 23, 1990 (Ref. definitions for piping, pressure vessel, evaporator, evaporator coil, condenser, and condenser coil. It also refers to paragraph 7.5.1 concerning strength of miscellaneous pressure containing parts and paragraph 9.4.1 concerning pressure vessel relief)
Interpretation IC 15-1989-3 – April 1992 (Ref. requirements for relief pressure protection in Section 9)
Interpretation IC 15-1989-4 – June 9, 1992 (Ref. requirements in 10.13.2.1 regarding refrigerant vapor alarms for Group 1 refrigerants)