Forum Discussion

Loren_Ross's avatar
Loren_Ross
Explorer
Aug 20, 2013

Water Pressure and Vent Issues

Our unit is 6 years old, and water pressure is getting very low. My gauge is showing 80# at the source, but inside the rig I have only about 30#. I can hold my hand over the faucet on full, and can hold the water flow. I've noticed a white crusty build-up on the inside of my outside hose connection and have scraped it off with a small screw driver, but I'm concerned that I may have this build-up throughout the system. Any suggestions on what I can use to flush the crud?

I also have no air vent from the gray tank. When I drain, the water will completely back up inside the drain hose and after almost 2 minutes, it will suddenly begin making a sucking sound and flowing again. I think it is building up so much pressure, it's sucking the P-trap in the shower dry to get air flowing. It has done this pretty much since it was new, but I never realized what was happening until recently when I noticed the smell coming from the shower drain when it had no water in it. I've tried to track the piping to see where it goes, but I cannot determine the path of the pipes. Suggestions on how to fix the vent?

Thanks in advance!
Loren
  • pkunk's avatar
    pkunk
    Explorer
    Aug 31, 2013
    I found screens on all my water feed connections on the bottom of the faucets. All were dirty and restricting the flow.
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 30, 2013
    doxiemom11 wrote:
    We had this after we had been in an area with high lime/calcium content in the water. We shut off the water and water heater, let the water cool and then drained the water heater. You would not believe how much crud came out of the heater. We then refilled and the problem was gone. The crud was getting into the lines every time we drew water.

    I get your point. We stayed in Parker last year and had the crud problem in the hot water heater too. I clean it with a flushing tool about every 3 months, and I always get a bunch of white colored crystalline chunks flushing out of it. After Parker, the chunks were dark brown, which matched the color of the water there.. It was pretty dirty stuff. Again, I'm thinking the back-flow preventer is probably plugged with the same white crystalline stuff that grows in the water heater. I've seen small deposits on the inlet when I disconnect to move, so it makes sense that the back-flow preventer is plugged. Thanks for the suggestion!!
    LR
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 30, 2013
    paulcardoza wrote:
    Do you have the same problem when on City Water AND Onboard Water (using the pump)?

    Actually, Paul, the water pump does a little better pressure-wise. But it's a pretty low pressure pump, so I have never had good pressure from it anyway. The city water connection has always been the best and now that its slowed so much I'm thinking the above suggestion to clean the back-flow preventer is probably the solution. I'm hoping to get on it next week, after the holiday.
    LR
  • doxiemom11's avatar
    doxiemom11
    Explorer II
    Aug 28, 2013
    We had this after we had been in an area with high lime/calcium content in the water. We shut off the water and water heater, let the water cool and then drained the water heater. You would not believe how much crud came out of the heater. We then refilled and the problem was gone. The crud was getting into the lines every time we drew water.
  • paulcardoza's avatar
    paulcardoza
    Explorer
    Aug 28, 2013
    Do you have the same problem when on City Water AND Onboard Water (using the pump)?
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 28, 2013
    eHoefler wrote:
    Check the vent pipe into the grey tank. If it is slid into a rubber collar at the top of the tank, slide it up and see how far it goes into the tank. My bet it has slid all the way to the bottom and is sealed off and not letting it breath.

    I have absolutely no way to get to the top of the gray tank, unless I completely remove it from underneath. I also have no access to any of the piping as they are installed inside the walls. The only way to get to them is to remove the interior walls, and I'm not prepared to try that one. You may be right, but I have no way to determine that one.
    LR
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 28, 2013
    louiskathy wrote:
    Have you unscrewed the faucet screen and cleaned that out?? Could just be clogged where the water comes out of the faucet.

    I've checked them Kathy, but they are all clean. I have the same low pressure in both sinks, the shower, and even the toilet barely dribbles when flushing. Thanks for the suggestion.
    LR
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 28, 2013
    98coachman wrote:
    You might check if they took out the test plug on the roof from when the unit was built. Good luck, Bill

    There's only one roof pipe, it splits off to the black and gray inside the walls. Since the black tank empties in 15 seconds flat, I'm pretty sure that there is no plug in the pipe. I installed one of those directional cyclone vent toppers on the pipe and saw no plug when I installed it.
    LR
  • Loren_Ross's avatar
    Loren_Ross
    Explorer
    Aug 28, 2013
    bob213 wrote:
    Low pressure(crud build-up) could be a bad inlet check valve. Check here to see how to fix it:
    inlet valve repair
    Don't know about vent issue.

    Excellent suggestion Bob, thanks!! I'll give it a go and see what happens.
    LR
  • eHoefler's avatar
    eHoefler
    Explorer II
    Aug 20, 2013
    Check the vent pipe into the grey tank. If it is slid into a rubber collar at the top of the tank, slide it up and see how far it goes into the tank. My bet it has slid all the way to the bottom and is sealed off and not letting it breath.

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