Forum Discussion

kampinggal's avatar
kampinggal
Explorer
Oct 06, 2014

Gray Water Holding Tank

We recently had to have the holding tank replaced due to a crack. Since replacing the tank, they have been back three times because the water is coming out of the bottom of the camper (when the valve is closed). I called the company that replaced the tank and they told me that we are overfilling the tank which is pressurizing the tank. They also couldn't find a problem and I don't think they really came out the third time when they said they did. We never had an issue with the first tank. We have had water back up into the tub, with the first tank and water never came out under the camper. This past weekend, the tank was not full (only had two showers in it) and the water was coming out of the bottom of the camper. So two things, I'm worried about the damage to the camper with the water coming out of the tank and out through the bottom of the camper and has anyone heard of this before? My next step is to call Jayco and tell them their recommended repair service company is not worth two pennies!
Seeking Advice
  • mobeewan's avatar
    mobeewan
    Explorer
    Oct 08, 2014
    Tank cannot be pressurized from just filling from the sink and tub drains. It would just fill until the tub backs up and overflows. No pressure it is just gravity filled and vented. Even if vent was clogged it would still fill to a certain point and them back up into the tub and overflow. At most there could only be about a half pound of pressure in the tank if the vent pipe becomes clogged due to a foot to 18 inches of head (pressure due to weight of water) above the tank. And this would be normal for a tank that has a closed valve that was full with water backed up into the tub.

    So they are full of it when they tell you the leak is because the tank is poressureized.

    There are 2 connection methods for the vent and fill connections on top of tank.

    One is female threaded fittings in the top of the tank with male fittings screws into them and the vent and fill pipes are glued to the male adapter fitting.

    The second connection method are holes cut in the top of the tank and a rubber grommet inserted into the holes, then the vent and fill pipes are pushed into the grommets which should become tight when the pipe is inserted.

    Potential problem is one of the following:

    Fill pipe not connected.

    No gasket or wrong fittings at fill pipe connection.

    Vent pipe not connected.

    No gasket or wrong fittings at vent pipe connection.

    "New" Grey Tank is cracked.

    Tank was never replaced and they tried to patch it.

    They did not loosen the vent pipe at the roof so they could drop it down so they could properly connect it to the new tank. Then reseal the pipe at the roof when the new tank is pushed back up into place along with the pipe. Did they go up on the roof?

    The same would need to happen with the tank fill pipe. Did they go into the cabinets or plumbing access for the tub and sink drain piping to disconnect that pipe above the floor?
  • downtheroad's avatar
    downtheroad
    Explorer
    Oct 06, 2014
    kampinggal wrote:
    I called the company that replaced the tank and they told me that we are overfilling the tank which is pressurizing the tank.


  • beemerphile1's avatar
    beemerphile1
    Explorer
    Oct 06, 2014
    kampinggal wrote:
    ...I called the company that replaced the tank and they told me that we are overfilling the tank which is pressurizing the tank....


    That is BS, if they correctly installed the tank it is vented through the roof and impossible to "pressurize".

    They probably don't have the vent or something else connected correctly. Either the tank is overflowing or a water line is dumping before the tank.

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