Dan,

I lack knowledge of Vogue specifics, but I suspect all our coaches share the need for pressure regulated air and unregulated air pressure.

For example, when your coach is running, the engine air compressor is providing 120 /130 PSI air to your auxiliary air system. That includes your entire coach suspension system. That is the system into which your auxiliary electric air compressor is plumbed. While not all coaches can be leveled with the air pressure from the aux compressor a lot can and are leveled, requiring at least 100 PSI.

That pressure however is too great for some of the aux air needs such as the air floor. Those components which could include the generator air bags, the bed lift, and pocket doors. Unregulated air may be required for the door lock and the air bellows for belt tensioning. Prevost definitely requires unregulated aux air pressure for those components, and in the case of the air bellows regulates them in the engine compartment. 45 PSI is not enough for them.

If you check your system you are likely to find you have both regulated and unregulated air pressure.

As to the running pump and the escaping air that could indicate the discharge pressure line from the pump may have failed and the system has a check valve to prevent the built up air from backflowing. I had that happen on my shop air supply once.