Please Help. I recently bought a Avenue 32 RLS with a washer/dryer in the closet. I tried to wash a load of clothes and water shot up the drainage pipe. The water is not making it to the black tank. I used a controlled flow of hot water and funneled it down the pipe. The water backed up to the top of the drain pipe. I went to the tank dumps and opened all tanks, with no water flowing out of the tanks. I went to the passenger side compartment and found a midline drain plug. I unscrewed the cap and the water dumped into a 5 gallon bucket. The water makes it to the cap, but will not proceed to the black tank. Im thinking there is a one way valve preventing septic back flow. Please help
Please Help: 23 Alliance Avenue 32RLS- Washer/Dryer Drainpipe Flooding
- Thread starter armycop89
- Start date
Sorry, I don't have an answer for you, but I have a question. Are you sure your washing machine drains to your black tank? In our 340RL it drains to the grey tank and in our prior RV (Heartland Bighorn) it also drained to the grey tank.
Did you purchase the RV new or used? Has the water ever drained properly?
Did you purchase the RV new or used? Has the water ever drained properly?
BryanValRox
Elite Member
Sorry, your having this issue folks.
I would think that your washer should be draining into your gray tank and not your black.
If you have found water at the midline drain plug that is a start. Have you considered inserting a plumbers snake or electric fish tape in at this point and see if it will push thru into the tank.
I would also think that there would be a TRAP in the line to prevent odor/gases from coming into the coach.
My take is the trap would be closer to the washer not the tank.
I am unaware of any check valve in the plumbing to prevent back up, water always seeks its own level, so given the tanks location(height) in the chassis the tank would need to be full before it would start backing up into the washer drain pipe.
I assume you have flow from your tank drains when you run water from other source? (Gray and Black). It so, it certainly would support some sort of restriction in that washer drain line that will need cleared out.
One word of caution, with running snakes/fishes in plumbing, RVs sometime use a flexible membrane style trap, these could be damaged or inverted during the snaking operation, so proceed with caution.
I would think that your washer should be draining into your gray tank and not your black.
If you have found water at the midline drain plug that is a start. Have you considered inserting a plumbers snake or electric fish tape in at this point and see if it will push thru into the tank.
I would also think that there would be a TRAP in the line to prevent odor/gases from coming into the coach.
My take is the trap would be closer to the washer not the tank.
I am unaware of any check valve in the plumbing to prevent back up, water always seeks its own level, so given the tanks location(height) in the chassis the tank would need to be full before it would start backing up into the washer drain pipe.
I assume you have flow from your tank drains when you run water from other source? (Gray and Black). It so, it certainly would support some sort of restriction in that washer drain line that will need cleared out.
One word of caution, with running snakes/fishes in plumbing, RVs sometime use a flexible membrane style trap, these could be damaged or inverted during the snaking operation, so proceed with caution.
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Yeah I found the inline p-less trap. I’m going to run a garden hose with a little more water pressure and an airline to try and force the lips. But the pipe between the membrane and the tank is still holding a large amount of water. I would rather not try pushing anything through the membrane 
Now that you have found this "p-trap" like device, you might simply contact Alliance for a replacment.
Here is the Owner Empowerment video from Alliance, talking about this device.
Here is the Owner Empowerment video from Alliance, talking about this device.
BryanValRox
Elite Member
Glad you found it,
I would agree with Jim, you should just replace it and sleep well knowing that it is new.
Given that it won’t flow, it could already be inverted, or swollen or just plain suck together from age and or use.
Not sure the previous history of your coach, but laundry detergent may have taken its toll on the membrane.