gray water pressurzing


Camping Kelly

New Member
when I use my sink, or shower the gray water tank starts seems to gets pressurized with air. The tank is not full, but it will start to drain very slowly or even stop draining. I have to open the gray water drain valve to relieve the water/air pressure that gets built up in the tank. I do not think the gray water tank has a vent like the black water tank. when I dry camp this becomes a problem. I have a 2004 Trail-Lite Class C.
 

Camping Kelly

New Member
Re: gray water pressurzing

when I use my sink, or shower the gray water tank starts seems to gets pressurized with air. The tank is not full, but it will start to drain very slowly or even stop draining. I have to open the gray water drain valve to relieve the water/air pressure that gets built up in the tank. I do not think the gray water tank has a vent like the black water tank. when I dry camp this becomes a problem. I have a 2004 Trail-Lite Class C.

Edited by Camping Kelly 7/28/2007 2:43 AM
 

Bush70

New Member
Re: gray water pressurzing

the tank has to have a vent. it may not go through the roof like the black. There may be back check valves under the sinks. They may not be working. I would start there. Good Luck
 

TexasClodhopper

Senior Member
Re: gray water pressurzing

Both of my tanks have a vent that goes through the top. You definately have a problem with the vent. The problem you are having is exactly what the vent is there for.

Check the roof for a vent cover that is over the shower area.

My shower floor is raised, and I have an access panel on the wall that when removed gives access to the area under the shower. That's where you might find a trap and the connection to the vent pipe. That will give you some idea where the vent is going.

It has to be vented outside or you would smell the inside of the gray tank.
 

Bush70

New Member
Re: gray water pressurzing

My grey has back checks and there is no outside vent. Also there is no smell.
 

Camping Kelly

New Member
Re: gray water pressurzing

I have checked the roof and there is no gray water vent only a black water vent. And the back flow vent under the sink only prevents air or water from going out. I had temporilary removed this once and a lot of air came out allowing the tank to depressurize, but I did put it back on not wanting water or the smell to come in the camper.
 

TexasClodhopper

Senior Member
Re: gray water pressurzing



Here's a diagram for my Winnie that shows the plumbing vent setup.

Plumbing Vents Winnie Gray/Black

I don't know how you can have a tank that doesn't have a vent. Your system might be different, but there should be a vent somewhere and it probably is stopped up.
 
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