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Jfet's avatar
Jfet
Explorer
May 17, 2013

gray water only connection help

I am doing cutouts in the siding on our camper build and I am at the point where I need to figure out a hatch and connection for our gray water tank. We are using the Thetford cassette toilet so we do not have a black water tank. We have 37 gallon fresh and 37 gallon gray.

The gray tank will just hold water from our sink, through a p-trap. We do not have an indoor shower.

I am looking at these 1-1/2 inch gate valve things. Is the setup just a pipe connection from the tank to the gate valve then from the gate valve to a 5/8" garden hose type connection, then on the other end of the garden hose a adapter to the 3" drain pipe that a dump station would have?

Like this: http://tweetys.com/wastevalvewmetalhandles1-12.aspx

And this: http://www.americanrvcompany.com/Camco-39322-Easy-Slip-Gray-Water-Seal-3-x-4-Inch-Camper-Trailer-RV

So our side hatch would need to be big enough to reach in and pull up the gate valve?
Truck Campers

5 Replies

  • Jfet's avatar
    Jfet
    Explorer
    May 20, 2013
    Thank you for the responses. I didn't know the gate valve came without the fittings for piping...that helps a lot.
  • AnEv942's avatar
    AnEv942
    Nomad
    May 17, 2013
    If you add a valve get one with the hubs included-what you linked is only replacement valve. (valve slips between & is bolted between hubs)

    http://www.rvpartsnation.com/product/1446/1-1-2-termination-valve

    From the Valterra site- hubs available seperatly...
    Unsure of termination as usually grey dumps into 3" black plumb and 3" bayonet fitting for cap/hose. Maybe end with 1 1/2 MA and use thread on 3/4 hose adapter.

    Like one of these? They show hub with 1 1/2 thread, http://www.valterra.com/RV/flanged_valve_fittings.htm
    if its 1 1/2 valve T1008-1 would bolt to valve outlet (instead on glue on hub) adapt to 1 1/2 thread then use cap with hose adapter http://www.valterra.com/RV/plumbing_fittings_and_accessorie.htm

    Would allow use of larger dump hose if wanted. Compartment also needs to be large enough to REMOVE the valve for future replacment.
  • nwjetboat's avatar
    nwjetboat
    Explorer
    May 17, 2013
    jimh425 wrote:
    Sometimes there is a short distance of pipe from the tank to the waste gate. I'd do that and make the lever accessible. Think about what happens if you need to repair/replace the gate in the future.



    X2 Just for the reason above. Have seen more than one post about how to fix a leaking gate...
  • jimh406's avatar
    jimh406
    Explorer III
    May 17, 2013
    Sometimes there is a short distance of pipe from the tank to the waste gate. I'd do that and make the lever accessible. Think about what happens if you need to repair/replace the gate in the future.
  • WyoTraveler's avatar
    WyoTraveler
    Explorer
    May 17, 2013
    Why not use a standard grey water valve? It may be easier to adapt to hose fitting with plastic gate valve because rv grey dumps into black outlet which you won't need. When I built a small camper I went from sink to hose outlet fitting with no holding tank. I carried a 5 gallon plastic container when we weren't in an rv park. I only used a 10 gallon fresh water tank. We used portable flush commode & showered in rv park.

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