CL300 & GLF
You attach the huffer to the external air inlet and ask for 50psi. You already have the GPU connected for electricity. Now the plane works exactly as if you have the APU running. The aircon works as normal. When you engage start the air is redirected to the airstart and the aircon shuts down.
The book implies it works but is vague. I asked at all the recurrents and no one could answer the question. But after one week with a U/S APU, it became apparent that the aircon works just fine with air from the external airstart inlet. All you are doing is filling the main gantry with pressurised air just like the APU bleed.
