The water fill on my 2007 Itasca Navion looks like this (circled, top left of photo):
I use a Culligan filter housing to feed the chlorine into the tank when filling, and attach one of those short sections of flex hose to the inlet as the first step, attaching the filter housing to the flex as Step 2 (flex shown, this time with arrows*):
The filter housing, by a lovely coincidence, is the right height to rest on the floor of the water utilities bay, so I can just screw the flex to the housing and move on from there (line filter, pressure regulator, water hose, plenty of other little bits to make it all fit).
It's occurred to me more than once that things would be easier if I just left the short length of flex permanently attached. Can anyone suggest why I shouldn't do that, or is it a fine thing to do? As shown in the picture, I would cap off the flex when I'm not filling the tank, to keep contaminants out.
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*I figured, one circle, some arrows, and a paragraph here because you can't see paragraphs on the back of an electronic picture, and I'd be set.