How to Clean RV Fresh Water Holding Tanks

How to Clean RV Fresh Water Holding Tanks
Sealed and often left stagnant under warm or hot conditions, the water tanks of an RV eventually become filthy with algae and slime. Being forced to drink or bathe in that foul-tasting stuff defeats the purpose of even having an RV with running water, so the tanks must necessary be cleaned every so often. The cleaning and sanitizing process is pretty easy, but consumes a lot of time and water.


Difficulty: Easy

Things You’ll Need:
  • Detergent Funnel Bleach
  • Detergent
  • Funnel
  • Bleach
Step 1
Look up how much water your RV's tank can hold in the owner's manual, as you will need that information later. Then take it with you, as it will prove handy for identifying other parts on the RV later.
Step 2
Find the water heater, which is usually situated behind a panel on the outside-rear of the RV. Turn it off and then also turn the pressure release valve to open. Then pull the plug or open the valve on the water heater to drain its tank, but be careful of any hot, scalding water. Finally, go to the water pump (sometimes located behind the same panel) and deactivate it too.
Step 3
Go to the RV's drainage lines. At their lowest point, there will be valves or plugs. Open these to drain whatever water is left in the tanks.
Step 4
Go back to all drainage valves or plugs and close them again.
Step 5
Go to the water tank's filling nozzle, insert a funnel, and put four teaspoons of detergent into the water tank for every ten gallons of water it holds.
Step 6
Connect the filling nozzle to a water source and fill the tank up with water.
Step 7
Switch the water heater and water pump back on, and close the pressure release valve.
Step 8
Go into the RV, turn the faucets on, and let the water run until soapy water comes out of them. Then shut them back off.
Step 9
Shut off the water heater and water pump, open the pressure release valve, and drain the RV's tanks, and seal everything back up, repeating Steps 2 through 4.
Step 10
Sanitize the water tanks by repeating Steps 5 through 8, only this time use bleach instead of detergent. Pour a quarter cup of standard bleach (adjust the amount downward if you use concentrated bleach) into the water tank for every fifteen gallons of water. Then leave the bleach-water in the tanks overnight (or at least twelve hours) before draining them. Otherwise, the procedure is the same.
Step 11
Refill the water tanks after emptying the bleach-water out of the tanks.
Step 12
Turn the faucets back on and let the water run through them, just to make sure there is no residual soap or bleach in the water lines. Let it run until there is no hint of soap or bleach scent in the water.

Tips & Warnings

The reason the cleaning and sanitizing are done in two separate stages is that mixing bleach with most household cleaners is dangerous. It is better to not take the risk of accidentally creating toxic gases and to simply keep them as separate as possible. Do not mix them together in a bucket to pour into the water tanks..

Article Written By Edwin Thomas

Edwin Thomas has been writing since 1997. His work has appeared in various online publications, including The Black Table, Proboxing-Fans and others. A travel blogger, editor and writer, Thomas has traveled from Argentina to Vietnam in pursuit of stories. He holds a Master of Arts in international affairs from American University.

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