Everything here is from the references shown below, with a few comments in an alternate color.
Bleed air pressure is less than 5 PSI.
(1) Altitude . . . Descend below 32,000 feet
WAI MUST BE ACTIVATED AND REACH AN OPERATING TEMPERATURE GREATER THAN 100°F PRIOR TO ENTRY INTO ICING CONDITIONS.
(2) WAI . . . ON
(3) ECS System . . . Monitor
Gulfstream GVII-G500 Airplane Flight Manual, Revision 4, August 29, 2019
Gulfstream GVII-G500 Production Aircraft Systems, Revision 3, July 15, 2019
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