2017 Legacy 38C low point drain location, I've attached pics of the utilities bay, as far as I can tell these valves just drain the fresh water lines in the coach and not the tank. I can drain the tank with the pump by running the shower and the grey tank but I'd rather not if I don't have to.
On my 2018 the fresh water tank drain is behind the individual hot water line drains shown in your pic. I cannot tell from your pic if there is anything back there. Have you looked closely there? Don't mean to insult you; it took me a while to discover it on my unit.
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SCFISHNMAN
US Army (Ret)
2018 Legacy SR 340 34A
North Carolina Mountains