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How To Clean/Sanitize RV Water System And Holding Tanks

How Do You Clean An RV Fresh Water Tank

If walk around a campground and ask everybody you meet how often they sanitize the water system and fresh water holding tank in their RV camper.

I bet less than half would even know what you’re talking about.

Related Product: keep your RV freshwater tank clean using a Beech Lane RV Dual Water Filter System (click to view on Amazon)

Sanitizing the RV water system is something everybody should do at least once a year.

If you take your camper out of storage or have had water sitting in the fresh water tank for months without being used and rinsed through, it should be sanitized for safety, smell, and taste reasons.

Sometimes you can tell just by smelling the water. If it smells strange, it’s time.

Keeping your RV tanks and water system/lines clean is important even if you don’t drink the water coming out of your faucets and shower.

If you use the water in any way, you should keep your water system and tanks clean.

This way you won’t end up with algae, slime or harmful bacteria issues which might end up costing you lots of money to replace your tanks and plumbing.

See Also: Best RV Water Hose For Drinking Water

A lot of people skip out on RV maintenance because it’s too much work, but sanitizing the water system is easy to do and requires more waiting than work.

Today we’re going to go over how it’s done.

How do you know when it’s time to clean/sanitize your RV water lines and system?

As mentioned above, if your camper has been sitting in storage, parked for months with water in the fresh water tank, or smells strange, it’s time to bring the bleach out!

You should even sanitize if you’ve visited a campground with suspicious smelling water.

The first thing you should do when you get out of there is to sanitize your water system.

Even if you only kept your water hose connected to the city water inlet on your camper.

The water has traveled through all of your pipes and might have left bacteria and microorganisms behind that will cause trouble later on.

We also recommend purchasing an RV filtration system that will clean the water before it enters your camper.

If you have a problem with algae or slime, it goes without saying that it’s time to do a thorough cleaning of your whole water system and all pipes.

How to clean/sanitize your RV water system/lines

Sanitizing your RV water system is a very easy and straightforward process.

It doesn’t take a lot of preparation or cost a lot of money. There are six things you’re going to need:

  • Access to potable water and place to dump the grey tank – Since we’re going to fill the fresh water tank and drain it several times, access to potable water and a place to dump that water is a necessity. See Also: How To Find Nearby RV Dump Stations & Fresh Water Fill-Up
  • A clean fresh water hose
  • Regular Bleach (Like Clorox) – This is what’s going to clean the whole water system thoroughly.
  • Funnel – Used to pour our bleach + water mix into the fresh water tank
  • One gallon container – You don’t want to dump bleach straight into your holding tank without mixing it with some water first.
  • 1/4 Cup Measuring Cup – We’re going to mix 1/4 cup of regular bleach with water for every 15 gallons of your fresh water holding tank. For example, 1 cup bleach for a 60-gallon holding tank.

Step 1: Make sure you’re not connected to city water

Step 2: Turn off the water pump and water heater, then drain the water heater.

This is done by removing the drain plug, often found in the lower left corner, usually accessed on the outside by opening the water heater door.

When empty, screw the drain plug back on.

There is normally a water heater bypass located where the water pipes go into it.

In order to stop the water heater from refilling again, you will need to access the inside of the water heater and turn off the hot and cold water pipes.

There should be a single valve between them you can open to bypass the heater.

Step 3: Drain the whole water system in your RV by turning on faucets and emptying the gray water tank.

Step 4: Bypass any internal or external filters. If not possible, change the filters when done sanitizing.

Step 5: Fill your fresh water tank with potable water until it’s about 1/3 full.

It doesn’t have to be exact, but we want it to be somewhat filled, although not all the way full.

Step 6: Now we’re going to make our bleach mix.

For every 15 gallons, we want 1/4 cup.

If you have a 45-gallon water tank, use 3/4 cup in total. Add bleach to the one-gallon container and then fill it up with potable water.

Step 7: Pour the mix you just made into your fresh water holding tank.

Then fill your fresh water tank with potable water until almost full.

Step 8: You can now open the water heater valves, turn on your water pump, and turn on one faucet at a time in your RV.

Let the bleach water run through your water lines until the water smells like bleach, then turn it off and do the next one.

You should be able to smell bleach after a minute or two.

Step 9: Now we have to wait. Waiting for at least 3 hours is recommended. I usually wait 12 hours to make sure the bleach can do its job.

Step 10: After X hours has passed it’s time to start the draining process.

Open the grey tank valve and empty it, leave it open during the draining process.

Step 11: Turn on your water pump and the faucets again. Let them run through your water lines until your fresh water holding tank is empty.

Step 12: Refill the fresh water holding tank with clean water, turn on faucets again, and repeat.

Refill and empty until the water coming out of your taps don’t smell like bleach anymore.

I also recommend draining the hot water heater again using the plug.

Step 13: When you can’t smell any bleach, you’re done!

Before you turn your water heater back on, make sure there is no air in it by turning on the hot water faucet in your kitchen sink.

It’s easy to damage the water heater if it’s turned on with air inside of it.

See Also: Best RV Water Hose For Drinking Water

Filling an RV freshwater tank
Make sure you fill the freshwater tank with potable water and bleach via the freshwater tank inlet and not the city water connection.

Frequently Asked Questions

If I add twice the amount of bleach, will it get done faster?

No, adding twice as much bleach won’t be any more effective and will not make it work harder and faster.

Don’t start the process if you don’t have enough time and won’t have access to potable water.

Can I put bleach in my black tank to clean and sanitize it?

I don’t recommend putting bleach in your black tank, but RV holding tank treatment like the Happy Campers Organic RV Holding Tank Treatment (click to view on Amazon) will help clean the black tank and break down anything left inside.

See Also: How To Maintain RV Holding Tanks To Prevent Clogs & Odors

What kind of bleach is best to sanitize the RV water system?

Chlorine bleach, non-scented and non-gel.

Can I dump bleach straight into my fresh water holding tank without mixing it with water first?

No, this won’t be good for your water lines and holding tank. Mix it with water first.

How to sanitize and clean the RV water system and lines without using bleach?

If you don’t want to use bleach, Camco sells a mixture they call TastePURE (click to view on Amazon) that you can use instead.

The instructions for how it’s done can be found on the container itself. I have seen these for sale at regular stores as well.

See Also: How To Install Solar Panel On RV Roof & Connect To Battery

How to sanitize RV water lines only and not fresh water holding tank?

If you only want to sanitize your campers water lines and not the freshwater holding tank, you can do so by pumping the bleach and water mix into your city water connection.

You’re going to need a portable water pump to do this.

You could also connect the water hose to your city water connection, fill the hose with the bleach and water mixture and hold the hose up so it stays in there, and then connect it to potable water and turn it on.

Then turn on your faucets until it smells like bleach, turn them off, and then let it sit for at least 3 hours before turning them on again.

Then just rinse the lines with the faucets open. Remember to have the grey tank valve open so it doesn’t overflow.

See Also: How To Maintain RV Holding Tanks To Prevent Clogs & Odors

How often should I sanitize my RV water system?

If you live fulltime in your RV, I recommend doing it twice a year.

If you only camp during the summer and bring your trailer out in the spring, do it once in the spring.

What RV water filtration system do you recommend?

We have a post on the best RV water filtration systems that you can find by clicking here!

How do I sanitize my RV sewer hose?

I sanitize my RV sewer hose with a mix of bleach and water.

I make a bleach + water mix and pour it into the sewer hose with a cap on one end.

Then I fill it with water until it’s pretty full, then put another cap on the open end.

Then I let it sit for an hour or two, and rinse it out with water.

If you don’t have caps and can do it this way, you can make the bleach and water mix in a bucket that can hold your whole sewer hose.

Submerge the entire sewer hose in the mix and leave it overnight, then spray it off and rinse through with water.

How do I sanitize my RV fresh water hose?

Sanitizing the RV fresh water hose to make sure it’s free from germs and bacteria can be done the same way as with the sewer hose.

Make a mix of bleach (about 1/4 cup) and water in a clean container and submerge the hose.

Leave it overnight and then spray off the hose and rinse through it.

See Also: Best Heated Water Hoses For RV Campers, Barns & Livestock

How dangerous is bleach to deal with?

Bleach isn’t toxic but can irritate eyes, skin, lungs, and mouth. You shouldn’t drink it.

You mostly have to be careful avoiding bleach to get onto your clothes as it will, as you might have guessed, bleach clothing and hair.

Also, make sure you don’t leave any bleach in the freshwater tank or water lines.

Even if you have to refill the tank and rinse a few times it’s worth it to get everything cleaned out.

My water system, lines, and hoses still smell like bleach after rinsing through all of them, what can I do?

If your RV water system, lines, or any hose still smell like bleach after rinsing through them several times, you can make a mix of 1/2 cup baking soda and a gallon of water.

Pour the mix into your fresh water holding tank and run your faucets so the mix can get into all RV water lines.

Let it sit for a couple of hours. Then run your taps until your tank is empty and refill.

With hoses, make a mix (possibly with several gallons) and submerge the hoses, leave for a couple of hours, then rinse through the hoses until it doesn’t smell like bleach anymore.

See Also: Best Portable Solar Panel Charger For RV Camper/Boondocking

Let me know if you have any questions about any of the processes we’ve gone through above by leaving a comment.

by Jenni
Jenni grew up in a small town in Idaho. With a family that loves camping, she has been towing trailers since a very young age.

3 thoughts on “How To Clean/Sanitize RV Water System And Holding Tanks”

  1. Does the bleach damage the plastic? I’ve always been told that bleach will damage the plastic in refrigerator and not to use it on plastic.


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