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Mako_Kupo's avatar
Mako_Kupo
Explorer
Oct 20, 2018

rv plumbing questions, really need help

hey guys, im back! the solar system is ready to be ordered monday, and now i am looking into installing my water system. i have questions.

-there is little room inside, and i wanted to keep my grey tank inside because i live full time in CT in my RV, and in CT we get very cold in the winter. if i stored my grey tank outside which is 15 gallons, how much pink anti freeze would i need per tank? there would only be about 1 foot of water line running from the motorhome to the tank(outside).
-can i stand my tank up in any direction? or does the fat hose on the bottom need to be on the bottom? can it be stood up vertically?
-does anyone have a diagram or picture that shows what each opening on the tank is for? there is a fat 1.5 or 2 inch hole center bottom middle, one more small opening next to it about half the diameter also along the bottom, and on the side top(same plane) two more openings. i dont know which is for what. if it makes it easier ill upload pictures.

more questions to come, thank you all!
  • Lwiddis wrote:
    Connecticut is no place to dilute RV antifreeze to save a buck or two.


    im not tryign to winterize it, i live in it full time, and need to be able to shower. i dont think i have the room for the tank inside, some pictures later should help
  • apologies i will be back with pictures for all of this today! thank you all!
  • Pictures would be very helpful


    Where did you get this tank?

    Grey tank
    S/B two 1.5" openings on top
    One for Roof Vent line
    One for sink drain line (which should also have an Air Admittance Valve just after sink 'P' trap

    S/B one 1.5" opening either on bottom (not common) or sidewall near bottom for dump line
    **Bottom drain not common due to limitations in location in RVs. Bottom drain would require tank to slope all 4 ways to bottom drain plus dump line then sticks down enough for elbow/slope to drain line which could cause it to hang way down.
    Easier to side drain.....slope tank towards drain hole and then dump line doesn't hang so low

    Sounds like you have a fresh water tank.
    Fill opening, vent opening, cold water line supply, overflow opening, drain opening etc


  • Connecticut is no place to dilute RV antifreeze to save a buck or two.
  • I don't know how you're draining your gray, but I think I'd try to keep it empty. RV AF is designed to be used full-strength, so there's that.
  • One opening should be for outside vent. You could use an under sink vent and cap this opening.
    One 1.5 or 2 inch is for the drain.
    The tank can be any direction as long as the drain is in the bottom and it is down hill from your fixtures.

    Have you though of using one of these portable tanks
    You may need as much as a gallon. This could be come pricey!

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