Fast Flow Pipe - learn about the best sewer hose around - Waste Master

Does Dumping the Black Tank 1st & the Gray Second, Clean the Hose?

Every RVer knows that dumping the Black water, then the Gray water is to insure any residual Black water will be flushed down with the Gray water—but is this really true? After we answer this age old question, stay tuned for information on the best sewer hose we’ve found that works wonders in keeping you and your RV clean.

Actually it is, providing your Gray water dump valve and drain piping is 3″. Unfortunately many RV manufacturers still use 1.5″ piping and valves on the Gray water tank outlets. What actually happens in this case, is that only a very small portion of the inside of the sewer hose is cleaned.  Probably looking a lot more like this

slow flow pipe - waste master best sewer hose system

But this theory of dumping the gray water second, assumes that the water flow goes a little more like this

fast flow pipe - waste master best sewer hose system

To get maximum hose flushing action, the Gray water exit valve and piping needs to be 3″.

Here are the reasons:

1. It takes 2.56 times longer to empty a 35 gallon tank through an 1.5″ hole than it does with

a 3″ hole.

2. With the overall flow slowed so much, the water doesnt rush down the hose as it should,

cleaning the whole interior of the hose.

3.  As your Gray tank fills, a scum forms on the top of the water, generated from soap, oils,

shampoo, toothpaste etc. When the valve is opened, the faster the water exits, the

more it creats a whirlpool sucking the scum out. This action is minimal to non existant

through a 1.5″ hole.

Converting your existing system from 1.5″ to 3″ on the Gray tanks can only be done if the Gray holsing tank has a 3″ collar with a 3″ to 1.5″ reducer in it. You will be able to tell by looking at it. The first sign is, there is a band clamp around the tank collar.

holding tank - best sewer hose question solved

Second is some white looking paste around the fitting area where the reducer was inserted. This material doesnt ever harden fully, so you can loosen the band clamp and by moving the reducer back and forth with pulling pressure on it and a little patience the reducer will come out. If your tank has a 1.5″ tank collar you are better off aborting the project.

If and when you look for a new RV, make sure you look to see the plumbing system detail, it is the area you do not like to go near, so be sure to check this area out before you buy. The devil is in the details and most folks buy the bling first, then are stuck with the issues that they didn’t look for in the first place. Finding the best sewer hose for you is also important, so do some research on various systems before getting something you won’t be able to use or clean.

For some great holding tank tips, be sure you have requested our 7 Essential RV Holding Tank Tips

As promised, here are the details of our favorite system aka the one with the best sewer hose! The Waste Master system provides an opportunity for greater cleanliness and less hassle. What a deal, right? Learn more by reading the product description here.

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Trackbacks & Pingbacks

  1. […] I have learned a lot about drains and RV tank venting from this site. When I need to do some upgrades it looks like they have some great products to do the job. Not sure about how to properly dump your tanks? They have a great article about that right here. […]

  2. […] you follow our “First in Last Out” procedure found here you will disconnect the hose from the RV, attach the plug and walk the hose out to the sewer […]

  3. […] dumping your holding tanks uneventful and as efficient as possible. We highly recommend reading our “First in Last out” rules of dumping your tanks. If all RVers used this method we would eliminate ground water contamination between the RV site […]

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