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RVer Beware, Don’t Neglect Your Black Tank Flush

If you want to keep the odors away in your RV, there’s one particular piece of routine maintenance that can help. It’s called your RV black tank flush.

If you’re not regularly flushing your RV’s black tank, it’s only a matter of time before you’ll find yourself in a stinky situation.

Today, we’re looking at how valuable a black tank flush can be for your RV. Let’s get started!

What Is a Black Tank Flush?

A black tank flush is a water inlet port that connects to your RV’s plumbing system. Using this port in combination with your standard dumping routine can reduce the chances of solid waste staying in your black tanks.

A black tank flush can help minimize the chances that you’ll experience odors emitting from your black tank and into your RV.

They do an important job, but they’re relatively easy to use.

Man Emptying RV Sewer at Dump Station After Camping

How Does An RV Black Tank Flush Work?

All you need to use your black tank flush is a water hose and a water source. While the risk of contamination is typically minimal, it’s wise to use a designated hose for flushing your tanks. 

Once you connect your designated water hose to your water source and RV, turning it on will pump water into your black tank. The water will travel through the hose and water lines into your black tank. Inside the black tank is a nozzle that sprays the water around your black tank.

This helps reduce the chances of paper and other solid particles staying inside your tank.

This is typically done after each trip to avoid any issues between trips. If done correctly, you can drastically reduce the chances of any odors infiltrating your RV.

Wanna know: Can you dump RV grey water on the ground?

How Long Does Black Tank Flush Take?

The time it takes to flush your black tank will depend on the size of your tanks and how often you’re flushing them. If you’re regularly flushing your tanks, it won’t take nearly as long compared to if you rarely flush your tanks.

Thoroughly flushing your black tank can add 5 to 10 minutes to the total time of dumping your tanks.

Using a clear elbow allows you to keep an eye on the status of your tanks. If the water flowing from your tanks is clear and free of any waste particles, it’s a good indication that you’ve thoroughly cleaned your tanks. Depending on your tank size, you can close your waste valve for several minutes and allow water to fill up the tank.

You can then open it so the rush of water can get any stubborn particles out of your black tank and into the sewer connection.

What Are The Benefits Of A Black Tank Flush? 

Using a black tank has a couple of benefits. The first benefit is eliminating the chances of odors in your RV. You don’t want to leave waste particles in your black tank, especially if you’re not planning to use your RV for weeks or months.

You may be in for a smelly surprise if the next time you go to use your RV.

A black tank flush can also help keep your RV tank sensors clean. Tank sensors in RVs are notorious for being inaccurate due to particles sticking to them.

If a piece of paper or other solid waste attaches to a tank sensor, it will provide an incorrect reading. It’s relatively common for RVers to dump their black tank, and their sensors will indicate that the tank is still full. Flushing the tank will often rid sensors of debris that could cause issues.

Keep in mind: Here’s the truth about RV-specific toilet paper.

Are There Any Disadvantages To A Black Tank Flush?

The only disadvantage to a black tank flush is that you have to watch how much water you’re putting into your tank. The worst thing you can do is connect a water hose to your black tank flush, turn the water source on, and forget about it.

If you do, the water will likely enter your RV through the nearest drain, come spilling out a roof air vent, and also build up pressure in the black tank and your sewer plumbing. Many RVers that make this mistake also make the mistake of trying to flush the toilet.

Flushing will release the pressure that’s built up in the plumbing system and will cause a geyser of several gallons of black water to come shooting out of your toilet and into your RV.

How Do You Unclog An RV Black Tank?

If solids have clumped together in your black tank, they can clog your black tank dump valve. The best way to eliminate a clog is to use plenty of water and a black tank chemical treatment.

These chemicals will attack and break down solid waste in your black tank. Using plenty of water when flushing helps accelerate the breaking down process.

One of the best practices for unclogging an RV black tank is to move your RV with plenty of water in the black tank. A combination of the chemical treatment, excess water, and the rocking and sloshing motion as your RV travels down the highway can rid most stubborn clogs in your RV.

Clogs are often the result of excessive amounts of toilet paper or using the wrong type of toilet paper. Regularly cleaning your tanks, using the septic-safe toilet paper, using plenty of water during each flush can help avoid clogs in your RV.

However, if one does occur and you’ve tried everything to get it unclogged, you may need to hire a professional.

Watch out: An RV poop pyramid will be a serious nightmare.

How Do You Winterize A Black Flush?

If you live in a climate that experiences sub-freezing temperatures, you want to winterize your RV at the end of each season. This protects your RV’s plumbing from cracks and other costly damage. Filling your water lines and faucets with RV-safe antifreeze is excellent but typically doesn’t protect your black water flush system.

A black water flush system is entirely separate from the rest of your water system. This is an often overlooked step in the winterization process for RVers. Because you’ll need to pump the RV-safe antifreeze into the black tank flush components, you’ll need an antifreeze hand pump to get the job done.

This is the most straightforward way to winterize your black tank flush, so it’s ready for your next camping season.

How Do I Know When My Black Tank Is Full?

Depending on the size of your tanks and how many people are using the restroom in your RV, it will typically take a week or so before your black tank is full. The longer you use your RV, the more you’ll get a feel for when you need to empty your black tank. However, one significant indication is a distinct “bubble” when flushing the toilet.

This air bubble occurs due to the increased pressure in the tank from a lack of available space. You don’t have to panic unless you don’t have a plan for dumping your tanks.

You can typically get by flushing the toilet several more times without any issues. If you do witness the bubble, it’s time to dump your tanks and give them a good flushing as well.

Should I Keep Water In My Black Tank? 

One of the biggest mistakes many RVers make is not keeping water in their black tank. After dumping your tanks, you want to add several gallons of water back into your black tank. You can do this by either using the black tank flush or holding the foot pedal open to a toilet.

Keeping water in your black tank allows solids that enter your black tank to break down and prevent the possibility of clogs.

A black tank flush can be a handy feature to keep your plumbing system running efficiently.

Make sure you’re regularly flushing your tank and keeping water in it, and you’ll likely avoid issues when it comes to clogs. You’ll also keep foul-smelling odors at bay as well.

How often do you flush your black tank?

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