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How to Unblock the Wastewater Tank on Your RV

Julie is an RV enthusiast with lots of helpful information for readers.

The waste water tank on CI Carioca RV Motorhome. The handle is the grey line you see right in the middle and it is attached to the black waste tank

The waste water tank on CI Carioca RV Motorhome. The handle is the grey line you see right in the middle and it is attached to the black waste tank

All About Your Wastewater Tank

All RV wastewater systems are different. But my personal experience/knowledge may still be useful to you. A clogged wastewater tank is a problem we encountered when we first got our RV motorhome. Depending on the exact problem with your waste water tank, this might not work for you. However, this is a good starting point before you spend money taking it to an RV repairs specialist.

We have a CI Carioca. Our waste water tank has a handle to pull to release. Some RVs have a button to press instead; however, provided you can get at the pipe that leads into the tank, this solution should still work.

Help! The Water Isn't Coming Out!

Our problem was that the tank was full, and we were pulling the handle, but nothing more than a tiny trickle of water was coming out! We surmised that it must be blocked, although we weren't sure.

We took it to a specialist, who was able to help us by telling us what we needed to do to sort out the problem. We got chatting to him, and he was kind enough not to charge us! He told us that this is a common problem and he sees it all the time, AND, it is really simple to fix!

Here is what he said. This is a common problem when an RV motorhome has been winterized, stored, and not used for a period of time. The plate that opens the waste water tank can become stuck and silt, etc., can block up the opening preventing the water from being released.

To Fix the Blockage in Your RV Wastewater Tank

To fix this problem there are three simple steps:

  1. Pull the handle to your tank firmly in and out several times to unstick the plate.
  2. Get a hosepipe and put it up the pipe that leads to the tank. Blast water into the tank. This will remove any blockages.
  3. Finally, use a little bit of blue chemical in the waste water tank. This is not something you would usually do as blue chemical is not for this purpose. However, as a strictly one-off measure for fixing this problem, the engineer said it is OK. Always check the rules of your campsite as many places do not allow you to empty blue chemical at the waste water disposal point. Instead, you will need to empty it at the chemical toilet point.

These three simple steps should solve the problem. However, if your problem persists, take your RV to a specialist.

Tips to Prevent Blockages in Your RV Motorhome Wastewater Tank

  • Never allow food waste to go down your kitchen sink into the waste pipe.
  • Especially avoid letting pasta cooking water go into the waste tank. This is really bad as the starch in the pasta can become like glue.
  • Don't wash boots in the sink.
  • Avoid getting anything gritty, muddy, or solid into the wastewater system.

Follow these tips and keep your wastewater system happy!

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2013 Julie Ritchie