How to Troubleshoot an RV Water Tank


Install a water filter on the fresh water intake hose to prevent sediment from settling in the hoses and tank.


Add water to the gray and black water tanks when not using the RV. This will stop the dump valves from drying, especially if the RV has been parked in the sun for an extended period.


Fill the fresh water system with 3/4 cup of bleach for each 50 gallons of holding storage. Allow the solution to stand for a few hours and then thoroughly flush the system with water. This will help sanitize the system. Take care not to leave any bleach in the tank as it could cause damage to the pump.


Check the RV electrical panel if the water pump does not run. Make sure to replace fuses with others of the exact same amperage. Make sure that the pump is turned on and check that the battery has a charge.


Leave the drain valves open and wait until the black water tank is full before dumping out. This way the force of the full tank will easily flush out any solids from the tank. With the valves left open, the solid waste could collect in the bottom of the tank and cause obstruction problems.

Tips and Warnings

  • You can purchase disposable water filters. Once the water flow begins to slow due to the filter becoming clogged, it is probably time to dispose of it.
  • Use of an approved water tank deodorant chemical for the black water will help breakdown any solid waste.
  • Do not travel with fully loaded water tanks because the movement of the water from side to side places a lot of strain on the tank and the mountings that hold it.
  • Using a little liquid chemical in the gray water tank to help with waste and odors, will also help lubricate the dump valves.
  • Some campgrounds require that you not use chemicals that contain formaldehyde because they can damage septic systems.
  • There is nothing like loading up the RV, closing the door, and heading out on the open road. These vehicles are completely self-contained units, and as such, you will need to stock up with plenty of water. There are three types of water tanks found on most RV's and motor homes. Fresh water, gray water and black water tanks. The gray water is for washing dishes and the black water is for the sewage system. Usually these tanks are sturdy and stand up to a lot of wear and tear, however, sometimes a problem can occur. There are a few troubleshooting steps you can take before calling an RV technician.