So you just need the adapter on the fresh water and quick flush,not city water? Then just put antifreeze in drains for p traps and some in toilet.? Plus make sure you have bypassed hwt remove drain?
Does your trailer have the city water connection (standard hose) as well as the big opening that you just put the hose into (doesn't screw into anything), like shown in the image below?
If so, the large opening (show on left in image below) is only for filling the holding tank...no need to blow air into this. You empty the holding tank by opening the drain valve, which is typically directly below the fresh water holding tank.
The city water connection is where you will attach the adapter. I remove the plug for the hot water heater and let it drain for a bit...then hit it will some air...helps speed up the process a bit.
Then I put the plug back in, and engage the bypass valve. Then I call my wife over to hold the hose to the adapter and I start the process of opening faucets. Once I have all that done, I move over to the quickie flush...hit it with air for a few seconds (very short water line). Put everything away...come back and pour antifreeze into the P-Traps. (sinks, and shower).
Grab a cold beer and call it a day.
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