Forum Discussion

omextreme's avatar
omextreme
Explorer
Nov 25, 2015

Merging grey tanks, is it possible?

Just a curious idea.

We are camping without sewer for the next 5 days, Our black tank will hold just fine but the grey tank for the shower will be an issue. We have 2 grey tanks 1 for shower and bath sink and the other is the kitchen and outdoor kitchen.

Here is my question. Both tanks have their own dump valve, both tanks are at the same height on the frame. And both tanks merge into the same pvc sewer pipe to exit the camper.

My Question is could I buy one of those gate valves that lock on to the end of the trailer sewer connection, close it and open the 2 dump valves on the grey tanks?

My theory is that both tanks would fill at the same time essentially doubling my shower water capacity, Kind of like a water level.

This seems to me like a great simple idea which probably means I am missing something.

Thanks for any advise
  • TucsonJim's avatar
    TucsonJim
    Explorer II
    Nov 25, 2015
    Another nice feature of having the Valterra valve on the dump outlet is that if any of your tank valves have a leak, you won't get a nasty shower when you pull the cap off to dump. BTW, I use one the valve to equalize our tanks too.
  • Hvyhauler's avatar
    Hvyhauler
    Explorer
    Nov 25, 2015
    It works for me... I've used this procedure before.I use a Valtera part # T58 twist on 3" waste valve (aka gate valve) and keep it capped on the end until dumping time.

    As others have said don't open the black tank valve while using this process.
  • JesLookin's avatar
    JesLookin
    Explorer
    Nov 25, 2015
    I glued one of those valves to the output, now share gray tanks with no problems
  • bg71361's avatar
    bg71361
    Explorer
    Nov 25, 2015
    I accomplished it by using this, install it closed and the pull both grey tank levers tanks will equalize. See link

    Click here
  • bdpreece's avatar
    bdpreece
    Explorer II
    Nov 25, 2015
    Sounds plausible. When I was being told how to use my Sani Con system, the dealer said I should empty the black tank then turn off the Sani Con and open the grey water to let it flush back into the black tank, then close the grey and continue to dump the black. You would be doing pretty much the same thing.
  • We_Cant_Wait's avatar
    We_Cant_Wait
    Explorer
    Nov 25, 2015
    That will work, just remember to CLOSE BOTH Grey Tank valves before opening the Black tank valve once the hose is hooked-up. This way you'll still have the grey water to flush the hose after dumping the black tank.

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