How to Pump the Chemical Toilet


Locate the black holding tank outlet pipe on your vehicle or toilet. In most instances, the cap is located toward the bottom or underneath the frame. It may, however, be above the black water or sewer tank.


Remove the cap from the pipe if there is a separate valve that keeps waste contained in the black water holding tank. Skip this step if there is no cap. Check your manual for specific instructions on how to proceed.


Place the flexible pump tubing from the pump truck or pumping station on the opening of the black water outlet pipe. Secure it as directed in your manual or by the instructions on the pumping unit.


Open the valve on the black water holding tank to release the liquid and solid waste from your chemical toilet, if necessary.


Turn on the pump truck or pumping station and draw all the waste out of the chemical toilet.


Close the valve, if necessary, to seal the black water holding tank. See your manual for the exact procedure used on your particular vehicle or toilet model.


Remove the pump tubing from the black water tank outlet and replace the cap, if applicable.

Tips and Warnings

  • Depending on the design of your chemical toilet, it may have only a black water tank cap, only a release valve or both.
  • Some types of chemical toilets will need to be refilled with water and chemicals after pumping to operate properly.
  • If your RV is stationary, you can attach the chemical toilet system to a drain or pump system and leave it there until you leave the facility. Black waste should, however, be accumulated for proper pumping and drainage.
  • Some chemical toilets may have a small holding tank that you can detach and manually drain.
  • Do not release the black water waste until the chemical toilet is properly attached to an approved pumping unit or drain.
  • Using cleaners not approved for chemical toilets can damage the unit and upset the balance in your black water holding tank.
  • Wash your hands immediately after pumping the chemical toilet to avoid disease and contamination.
  • Running water and indoor plumbing are amenities that are largely taken for granted. While it is virtually impossible to find a modern home not hooked up to these services, there are times when you will need to use alternatives to modern plumbing. Chemical toilets are used in boats, RVs and airplanes, for example. Portable toilets are also characterized as chemical toilets. These are the perfect compromise when water resources are limited. The holding tanks can only hold so much, however, and will eventually need to be pumped.