No matter how much you flush, nothing goes down your RV toilet? Then that is likely because the dried poop has clogged up your RV’s black water tank.
Don’t worry, as long as you haven’t dumped anything awkward inside 😉 the problem is fixable in most cases.
Read on as we share with you a complete guide on how to get the dried poop out of your RV tank and some prevention tips. But first, let’s see the causes of this problem and how to identify them so that you can have a better understanding.
What Causes Dried Poop To Clog The RV Black Water Tank?
The main reason poop dries up and forms a pyramid in the black tank is by leaving the black tank valves open. Generally, when an RV is connected to full hookup campsites, and the black tank valve is open, all the water goes to the sewer drain, leaving solid waste.
And you need to know about the funny term “Poop Pyramid.” Hmm, you guessed it right 😉
A poop pyramid is a pyramid of poop and toilet paper built upon the black water tank floor. Over time, this poop pyramid causes blockage in the bottom of the toilet line.
This problem generally happens with RVers in the hookup campsites who think that all the waste will easily flow away right into the drain sewer.
But the shape of the black water tank is usually flat at the bottom. So when you flush the toilet, water generally trickles away, leaving a dry tank behind. Since there is no water, the poop tends to pile up just underneath the toilet line.
The solid waste can’t slide up to the bottom of the tank because there remains no liquid in the tank. Moreover, the toilet paper acts as a binding agent and keeps the pile together.
All these ultimately enhance the growth of this poop pyramid until it touches the toilet line and causes the blockage.
How To Identify What Is Causing Blockage In The Black Water Tank?
Before you start applying the fix, you need to know what type of clog you have in the tank. Not just the poop pyramid, but there can also be other issues that cause the clogging in the RV black tank.
The pyramid plug and a blockage in the plumbing line have the same symptoms. So it is crucial to know the right cause and apply the solution accordingly.
When an RV Toilet clogs, there could be any of the following mentioned reasons:
#1. Poop Pyramid:
A Pyramid of poop and toilet paper builds up, causing the toilet clog issue. We already discussed this topic earlier, so not going into much detail here.
#2. Blockage In Toilet Line:
A blocked toilet line happens when solid waste and toilet paper trap in the pipe that goes from the toilet bowl to the black water tank.
Since the passage line is blocked, the waste material can now not move out to the black tank. This problem mainly happens in the RVs where the toilet is not directly situated above the black tank. In such designs, the pipe likely has turns and elbows which get clogged.
#3. Misreading Sensors:
Sometimes, when the tank sensors get caked with dirt and waste, they may indicate false readings about having a clog. When this problem occurs, you need to clean the sensors properly.
#4. Compacted Tank Issue:
The compacted tank issue occurs when solid waste settles and accumulates in the bottom of the black tank. It prevents the exit of the waste from the tank when you open the black tank valve.
Some of the reasons why this issue occurs are:
- Not using adequate water in the tank.
- The waste got enough time to settle in the tank while the tank was being stored. And that means all the liquid from the waste likely evaporated, leaving behind the dried poop and waste matter. This leads to difficulty while cleaning the tank.
- Not using the best quality water digesting treatment.
- Leaky discharge valve.
To identify and diagnose the issue, add some water to the RV black tank through the RV toilet bowl. Then, follow this table:
| Symptoms: | Problem Diagnosis |
| Water quickly accumulates in the toilet bowl, and the Black water tank valve was kept open for any period. | Poop Pyramid |
| Water quickly accumulates in the toilet bowl, and the Black water tank valve was kept Closed. | Blockage In Toilet Line |
| Added water quickly flows into the black water tank, and water flows out of the tank when the black valve is opened. | Misreading Sensors |
| Added water quickly flows into the black water tank, and Nothing comes even when the black valve is opened. | Compacted Tank Issue |
It is essential to correctly diagnose the cause before applying any fix because each type of clog can have a slightly different fix.
Here’s How To Get Dried Poop Out Of RV Tank:
To get dried poop out of the RV tank, you need to soften it using any kind of RV black tank treating agent. So firstly, close the black tank valve, add the cleaning agent, and let it sit for some time as per the manufacturer’s directions. After the given time, flush out the tank.
How To Fix A Poop Pyramid In The Tank?
- Firstly, close the black water tank valve.
- Then add any treatment or enzyme that helps liquify and clean away the dried deposits. For example, you can purchase something like this (available on Amazon).
- If the blocked channels down the toilet line open up, you can further add water and allow the enzyme to do its work. Then, based on what manufacturers of the enzyme suggest, let it sit there and properly function.
- If the channels are blocked and not opening, you can also use something like a PEX pipe and manually open up the blocked channels.
- After the required time for the cleaning agent to perform its action, you can flush out the tank. You should now notice everything is working properly, but you can repeat the process once again to be extra sure. This way, you can ensure that all the solid wastes are dissolved properly.
How To Fix Toilet Line Blockage?
- If the toilet line is blocked, you can try plunging it using a toilet plunger (just as you would do with your home toilets) to get rid of the blockage in the line.
- However, if that doesn’t work, you can use treating enzymes and the PEX pipe to clear out the clog from the line.
How To Fix a Compacted Tank Issue?
- To fix the compacted tank issue, you need to add the treating agent and let it sit in the tank until it dissolves the dried-up waste in the tank.
- Then, once the adequate time is given, you can dump the tank at any RV dump station.
How To Fix Misreading Sensors Problem?
- If the problem is misreading sensors, you need to clean them.
- You can use any cleaning agent like this Unique Sensor Cleaner Liquid (available on Amazon). It breaks down and dissolves the waste that is sticking to the sensors so that they can start functioning properly again.
- However, even after repeated cleaning and treatment, if the sensors malfunction, it would be good to just repair or replace them.
How To Prevent Dried Poop To Clog The RV Black Water Tank?
Here are some tips you can follow to prevent dried poop from clogging up the RV toilet next time:
- While you are at a full hookup site, don’t leave the black tank open.
- Generously use water with each flush because water is your best friend in avoiding any solid waste build-up in the tank.
- Use toilet papers that are RV-safe.
- Regularly and timely discard the wastes out of your black tank.
- Use black water tank treatment cleaning agents as per the requirement.
Final Thoughts
To get the dried poop out of the tank, you need some cleaning agent to make it soft.
You may have to take the help of additional equipment like a PEX pipe or something else to poke and open up the blocked channel.
Once you allow enough time for the cleaning agent to work on the solid wastes, you can discard the waste from the tank.
Remember to properly identify the root cause of the problem and apply the fix based on that. Hope that helps!
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