I can only tell you how mine work on my Freightliner chasis. When I hit the switch to dump the bags I hear the loud hiss of the air being released and the motorhome starts to settle fairly quickly. It leaves no doubt that the switch works as advertised. If I don't dump the air when I go outside I can hear a low hiss where the air is leaking out. It's done that since new and my understanding is that's normal. I've never timed it so I don't know how long it takes, but eventually all the air drains on it's own and the motorhome settles down to the stops.