How to Get Rid of Black Tank Odor

If you own an RV, you’re almost definitely going to have problems with a smelly black water tank at one point or another. After all, the things you put into that tank are far from pleasant, and this tends to lead to less-than-pleasant odors, especially during the warmer months when people like to go camping.

Some people think the best way to deal with this problem is to avoid using their RV bathroom altogether. This is, of course, ridiculous. You paid good money for your home-on-wheels, and you should be able to use every part of it.

Fortunately, there are plenty of ways to get rid of even the worst black water tank smell, meaning you can rest easy while using your handy take-along toilet. Not only that, but once you do get rid of any smells, there are also some simple steps you can take to avoid that black tank smell for the rest of your camping career.

Ready to get started and help your RV smell nice again? Let’s do it!

Photo by Aqua Mechanic

Potential Causes of RV Black Tank Smell in Your RV

First, let’s discuss the potential causes of any black tank smell in your RV. Obviously, the tank itself isn’t going to smell great, but those smells should be staying in the tank, not wafting up into your tiny bathroom.

There are four common reasons for this problem, and sometimes two or more will work in tandem to create an extra big camper black tank smell problem:

  1. Full tank
  2. Blocked vent
  3. Leaky toilet seal
  4. Buildup in tank

Fortunately, all of these issues are correctable, and most are super easy to fix.

How to Get Rid of Holding Tank Odor

Now that you know what might be causing your smelly problems, we can talk about how to get rid of RV holding tank odor issues.

Dumping the Tank

The most obvious step that everyone should try before taking any drastic measures is to dump the black water tank. Even if you don’t think the tank is full enough to be causing smell issues, the combination of outdoor temperature and what’s been put into the tank could definitely lead to problems.

When dumping, stand outside and make sure you hear a good amount of water leave the tank. If you don’t, you may have buildup in your tank causing a clog. (We will discuss how to deal with this issue in the next section.)

Unblocking the Tank Vent

Another thing you can try is cleaning out the tank vent. This vent is located on the roof and can become blocked up. Because this vent is where smells are supposed to escape, this can cause those same smells to vent into your RV instead.

To check and unclog your black tank vent, simply put a garden hose down the vent and run a strong stream of water through it. Just make sure your black tank dump valve is open and that you don’t have any kind of clog that could cause the tank to back up into your bathroom.

Check the Toilet Seal

Finally, there is the possibility of a leaking seal inside the bowl of your toilet. This leaves your toilet bowl dry and allows scents to make their way into your RV.

The first thing you should try if you believe this to be your problem is a good-sized helping of petroleum jelly applied to the seal when it is dry. If this doesn’t work, you may need to replace the seal entirely.

Photo by Cathy T

RV Black Water Tank Cleaning

If none of the above solutions work and you’re still wondering how to get rid of the smell in your black water tank, you probably need to give your tank a good cleaning to remove buildup and potential clogs.

There are a number of ways to clean an RV holding tank. However, we like to use a combination of methods that, when used together, always send RV black water tank smells packing.

Step 1: To begin, you will need to get rid of any clogs you may be dealing with. This can usually be done using a tool such as this one to spray water up into the pipes and loosen the clog. This will allow you to dump the tank—an important step, as the tank needs to be completely empty to start the cleaning process.

Step 2: Once your tank is empty, fill it all the way back up with clean water using the back-spray tool to provide good water pressure and help get rid of any buildup. Dump this water, then fill again. Repeat this process until the water being dumped runs clear.

Step 3: When you reach the point that all buildup has been removed from the tank and clear water is running from it, close the dump valve and fill the tank about ¼ full with fresh water using the flush valve inside the RV. Add tank cleaning chemicals to this water and go for a short drive to allow the mixture to slosh around the tank and give it a good cleaning.

Keeping Your Black Water Tank Odor-Free

Now that you know how to eliminate smell in an RV black water tank, you probably want to make sure you keep your tank as odor-free as possible from now on. Here are our tips for doing just that:

  • Always leave the black tank dump valve closed unless you are actively dumping. Leaving it open can cause problems with buildup of solids.
  • Lubricate your toilet bowl seal with petroleum jelly often.
  • Rinse your black tank vent every time you clean and reseal your roof.
  • Rinse your black tank until the water runs clear every time you dump your tanks.
  • Use plenty of water when flushing your RV toilet.

What do you think?