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Onboard water tank issue

Discussion in 'Luhrs Yacht' started by Rich Plukas, May 10, 2020.

  1. Rich Plukas

    Rich Plukas New Member

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    Feb 10, 2020
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    Location:
    Rochester, NY
    1999 Luhrs 360. When I am on the boat and have my city water hooked up it keeps filling my water tanks. I hate running that heavy. I replaced the water intake and pressure regulator about 2 years ago could that be failing already and be the cause of the tanks filling?
  2. Pascal

    Pascal Senior Member

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    What kind of pump? If a commonly used diaphragm pump then water should not back flow to the tank. Other pumps may allow water to flow back in that case a check valve at the pump inlet or outlet should solve the problem

    personally I never hook up to dock water in case of a plumbing failure and to keep the tank fresh
  3. chesapeake46

    chesapeake46 Senior Member

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    I've got a regulator and check valves between the tanks and the dock side inlet. Maybe your check valve has failed btwn the inlet and tanks.
    The house pump cant push water out the inlet and the dockside can't push water into the tanks.
  4. d_meister

    d_meister Senior Member

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    Do the fresh water tanks overflow? It would seem that if there is backflow through the tank outlet and pump circuit, there would be water flowing out of the vents at some point. Also, if there is an issue where the pressurized house system bleeds back into the tank, there should be other symptoms like excessive pump cycling when disconnected from shore water.
    Otherwise, there could be a tank fill plumbing circuit that has a full shut-off. If that is the case, it could probably be shut off with a valve to prevent filling the tank.
  5. Rich Plukas

    Rich Plukas New Member

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    Thanks, even though regulator is relatively new that appears to be the only thing between the incoming water and the tanks- I'll replace that again.
  6. Rich Plukas

    Rich Plukas New Member

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    Thank you for the info. I ONLY run water from the dock when I'm on the boat- but like the fresher water for washing and showers.
  7. rtrafford

    rtrafford Senior Member

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    If you're going to replace it, why not consider adding a ball valve to the plumbing for the certain ability of shutting off access to your tanks??
  8. cleanslate

    cleanslate Senior Member

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    What he said...check check one two..check the check valve. It's probably an in-line plastic unit.
  9. cleanslate

    cleanslate Senior Member

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    I would say there is an in-line check valve somewhere in the line . Could be near a Tee that splits the incoming water to go to the boats system and by pass the water tank. Probably in the bilge near the 12 volt water pump and tank.
  10. Pascal

    Pascal Senior Member

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    Again, what kind of pump? If a diaphragm pump, they have built in check valves. If one of them has debris keeping it open, you may not notice the pressure loss but it will allow water to flow back