One area of your RV that everyone dislikes is the sewage system. P.U.! Who wants that job? Fortunately, with the right combination of products and method, this doesn’t have to be a foul experience

By Paul Charlier

Got a question? Drop me an email! Paul Charlier Runs Premier Mobile RV

We love the convenience of having toilet, shower etc. in our RV but when it comes to dumping it, well no one really likes to do it, it’s kind of a crappy job!
If you are using your system correctly, then the evacuation process can go smoothly at the dump station.

The first thing I’d like address is what you do when you’re at a full-service site that offers a sewage drain at your site.

Many people make a really big mistake of pulling their valve handles open and leaving it open the whole time they are in the site. This is a huge mistake and can cost you a good dollar to remedy it. The problem is that all the liquid runs out while the paper and waste pile up! Not sure what I mean? Just look down any outhouse hole and what you see is what you get! Trying to get that mountain of waste out of your tank can be extremely time consuming or can cost $300 or more if you require a vac truck to come and suck it out. Never pull both your valves open, wait until they are full and you will avoid this huge mistake. And yes, I recommend doing this with the grey water tank as well, bits of food that go down your sink drain can get stuck and dry up in there as well. Although it’s easier to rinse out, it’s still good practice to keep a cleaner odourless tank.

There are basically two sewage tanks in your RV, a black tank (toilet waste) and a grey tank (shower & sink waste). The toilet waste is really the only one that most of us hate dealing with. The first thing you want to do is add a reliable toilet chemical to the tank via the toilet bowl along with approximately a couple gallons of water to get it ready. There are so many types of chemicals out there and almost every department store now sells them.

My personal favourite is T-5 by Monochem, they have been making T-5 for more than 55 years and as far as I’m concerned, they do it the best. I find it to be very good at breaking down the waste and eliminating the sewer smell. Some other products out there may work just fine, but I am a creature of habit and stick with what has never let me down in the past.

Other products include toss-ins pouches and various liquid products. Some of them you may have to use extra to get them to work as well.  Some pros and cons to liquids, toss-ins and powders really just comes down to convenience.

A clear adaptor for your sewer hose is a worthwhile investment.

Liquids can spill, powders can scratch the blade and seal on your toilet, so caution is needed when using them as to not get any on the blade when pouring it in. T-5 is such a powder but when properly put in with water it is no problem. The blade and seal is what keeps water in the bowl when in use, acting like a p-trap and keeping the odours from escaping the tank. No water in the bowl and your RV will quickly smell like an outhouse!

Every time you flush, air from the tank rises up through the bowl and into the RV, so having a good toilet chemical not only breaks down your sewage it makes it smell better too! Some chemicals do better at covering smell than they do at breaking down sewage so choose your chemical wisely. Cheaper is not always better.

Another main ingredient needed to make the sewage evacuation process trouble free is toilet paper. The only thing you should be using is RV toilet paper! It might cost a bit more than your regular household paper, but it’s designed to break down in water without clogging up. It comes in 2ply and single ply, for obvious reasons I would definitely recommend the 2ply! Also, never throw anything else down the toilet! Kleenex, feminine hygiene products and other materials do not breakdown and will cause a problem for you in the long run.

Be sure to buy RV specific toilet paper!

Lastly and probably most importantly is water! Use lots of water when flushing! The more water you have going in the black tank the better. The rule of thumb I have always used is to count to five (1 one thousand, 2 one thousand etc. etc..) after you flush. That way when it’s time to pull the big black valve handle at the dump station, everything can run out as quickly as possible without any clog ups.

Having a tank rinser installed on your black tank is also a good idea to help clean out any remaining bits and pieces. A less expensive alternative is a tank wand, which is basically a pipe you hook to a garden hose. It has a jet on the end that goes down the toilet which shoots a hard stream of water to help evacuate waste in your tank and helps keep your tank monitoring system working better by getting the bits of paper off of the probes inside the tank. 

When dumping, always dump your black tank first, it’s the dirtiest one so it’s the best one to start with. I use a clear adapter on my sewer hose, so I can visually see when the little bits and pieces are finished flowing out so that when I close the valve, I know I’m not pinching any bits of sewage into the gate valve seal which can cause seepage when the valve is closed. You will know you have this problem when you take the cap off and get a gross surprise all over your hand! Ew!

Once the black tank is drained you can then pull your grey water valve and let that less dirty water rinse out your hose. My wife has a job in this process as well, when I begin the grey water evacuation I knock on the exterior wall and she is ready in the bathroom with five-gallon jug of water that she pours in the toilet. After the grey water tank is emptied I then give the black tank valve one more pull which will rinse away anything left that didn’t make it out on the first dump. Alternatively, you can hook up the tank flushing system or a tank wand to the dump stations water supply (if they have one) but I do the five-gallon jug because it’s a much quicker process for me.

Lastly, be sure to have some wet wipes in your tow vehicle, so you can wash up your hands when done! Some people use disposable rubber gloves for the whole process and once I have even seen someone putting on rain pants and a rain jacket and gloves, I chuckled and thought this poor guy must have had a bad experience to go through all that trouble! Whatever equipment you choose to wear, be sure to have something handy!

If you use a combination of toilet chemicals, RV toilet paper, lots of water and a good quality sewer hose with a clear adaptor, along with my simple five-gallon method, dumping your seweage system will be as easy and as pleasurable as it can possibly be! W

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