Steps For Dumping An RV Blackwater Holding Tank

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As you are out camping at an RV park, the time has come to dump the contents of your black water holding tank. These are the recommended steps required to properly empty and rinse your holding tank.

List Of Supplies 

• Gloves
• Sewer discharge hose (we recommend one which is rigid and holds its form like the Camco RhinoFLEX hose)
• RV sewer hose support (such as the Camco Sidewinder)
• Garden hose (we recommend a hose different from the one you use for fresh water)
• RV rinse wand or built-in/ onboard tank rinsing system
• A high-quality holding tank treatment (like Unique Camping + Marine RV Digest-It Plus)

Step By Step Instructions 

Dumping your RV black water holding tank

• Rest the sewer discharge hose on the sewer hose support to allow slope from the RV to the sewer port.

• Ensure that your sewer discharge hose is firmly connected to the RV and securely inserted in the sewer drain opening. Sometimes having some additional weight on the hose can keep the hose from popping out of the sewer port with the pressure from opening one of the holding tank valves.

• Remove the bend in the sewer discharge hose that forms a P trap in order to allow the water to flow into the sewer drain opening.

• Close the gray water holding tank valve.

• Open the black water holding tank valve and wait for all of the contents to drain into the sewer port.

• Close the black water holding tank valve and open the gray water valve to allow the gray water to rinse the sewer hose while the gray water holding tank is also being dumped.

• Close the gray water holding tank valve.

Rinsing your RV black water holding tank

• Connect one end of a garden hose to the water supply and the other end to either the rinse wand or the built-in/ onboard RV tank rinsing system. 
• Opening the black water holding tank valve while using the onboard rinsing system is recommended by most RV manufactures currently. However, if you have the ability to monitor the liquid level in the holding tank by either having someone checking the sensors or looking into the RV toilet to see where the water level is at, it is possible to use the rinsing system without leaving the valve open. Allowing the water level to build up in the tank rather than allowing the water to drain out immediately can lead to a better cleaned out holding tank overall. Use caution if you choose to rinse with the valve in the closed position. 
• Rinse the black water holding tank. We recommend rinsing your tank every time you dump the tank. if possible and no lines are present at a dump station. If you need to wait until the next time you need to dump the black tank because of a line, then be sure and rinse the tank to make sure you get as much waste and paper out of the tank as possible. 
• Allow the water to drain out of the black water holding tank and into the sewer drain opening

Preparing your RV black water holding tank for use

• Close the black tank valve.

• Put the P-trap bend back in the sewer hose, adding water to the P-trap.

• If you are at a dump station, remove the sewer discharge hose and put the cap back on the discharge port.

• Go into the RV bathroom and hold the flush pedal down all the way to the floor for a full minute. This will allow 3-5 gallons of water into the black water holding tank (depending on the gallons per minute rating of the water pump on your RV).

• Add a high-quality bacteria-based holding tank treatment into the toilet with some water in the bowl, and then flush it into the black water holding tank.

• Hold the flush pedal down just enough to allow water refill the toilet bowl without draining it into the holding tank. This will create a vapor barrier between the black water holding tank and the rest of the RV in order to keep odors away. 
• The toilet is now ready to use again.

You have successfully dumped your RV black water holding tank! Well done!

If you’d like to check out how to dump the gray water holding tank, check out this article!

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