A very important part of maintaining your RV has to do with ensuring that your freshwater is always clean, which is why you want to keep your tanks sanitized.

Owning an RV comes with a lot of responsibility and it can be easy to overlook some components of your vehicle’s upkeep, as there is a lot to keep in mind. One thing that a lot of people tend to neglect or completely forget about is their freshwater tanks, which can result in you consuming unsanitary water if you are not careful.

To clean & sanitize your RV fresh water tank you will need bleach, a measuring cup, a funnel, and access to clean potable water. To begin, bypass your water heater and drain all freshwater from your tank. Then add bleach and flush the system with water until all traces have fully drained.

RV travel is as popular as it ever has been in the past, as we have been seeing record numbers in sales for recreational vehicles in recent years. This is the ultimate way to travel through the United States, as it enables you to have a very intimate experience with the country and all of its incredible landscapes - all in the comfort of your very own home on wheels. However, it is important to recognize that traveling in an RV is a lot different than doing so in a standard vehicle. RVs are much more dynamic and complex than your average car as there are so many components and features to be aware of. These are the things that make an RV feel homey but you must understand that all of these parts and components need special attention and upkeep to stay functional. There is a lot to keep track of but one thing that you certainly do not want to overlook is cleaning and sanitizing your freshwater tank. To help you understand this further, we are going to take you through the whole process of how to keep your RV’s freshwater sanitary.

After extensively researching RVs, I have been able to gather enough information to determine how to clean and sanitize the fresh water tanks of these vehicles. My research has taught me that it is better to sanitize your tanks routinely - before they get dirty.



Why Keeping Your Freshwater Tanks Clean is Important

When you are on the road, you need to keep in mind that you are going to be predominantly relying on your RV’s freshwater for a lot of different things - including consumption. It is easy to assume that because you are keeping all of your freshwater separate from your grey and blackwater tanks that it is going to always be clean and sanitary.

This is not the case. Freshwater tanks will start to form bacteria over time and become dirty. A lot of people neglect this part of their RV maintenance and end up drinking poor quality water that may even be dangerous for consumption. This can not only result in you drinking water that tastes bad but it also has the potential to pose health risks for you and everyone on board.

If you do not drink your RV’s water, then you may be thinking that it is not so necessary to have it be 100% clean and sanitary. However, odds are that you do still use it for washing your dishes and showering. At the end of the day, having clean and sanitary water does not require a lot of work and you can ensure that you have safe water for all purposes by periodically following a very simple maintenance procedure.

When to Clean & Sanitize RV Fresh Water Tanks

There can be some discrepancies about when you need to sanitize your RV’s freshwater tank. A lot of people say that you should only do so once a year or at the start of a camping season.

However, you should actually be cleaning and sanitizing your RV’s freshwater tanks at least twice a year. As a general rule of thumb, a good standard to hold yourself to is doing it every 6 months. But ultimately, you should clean and sanitize your tanks as often as needed.

Each person has a slightly different RV and puts it through different conditions. There are a lot of factors that contribute to how often you need to clean and sanitize your fresh water tanks such as:

  • Water quality (where you fill up)
  • Hot climate
  • RV age

If you have just bought a brand new RV, are traveling in a cooler climate region, and are totally confident that the water you filled up is clean, then you can count on your freshwater tanks staying sanitary for longer. However, some of these factors can be hard to gauge and predict, which is why it is best to stick to a 6-month standard to be on the safe side.

With that being said, observing the water quality that comes out of your freshwater tank is something that you should be doing regularly - regardless of external factors. You may find that your tanks need to be cleaned even more often than twice a year. If you happen to notice any scents or foul odors, it’s a good sign that it is time to sanitize your tanks.

In addition, if you ever notice that it has a bad taste or perhaps that the water is even discolored, murky, or has any kind of sediment, you should absolutely give your tanks a clean, as this implies that you have contaminated water. The last thing you want to deal with while traveling is an upset stomach due to unsanitary water from your RV’s tank, which is why you want to be vigilant with keeping things as sanitary as possible when on the road.

Cleaning & Sanitizing RV Freshwater Tanks

The nice thing about cleaning your freshwater tank is that it is a lot less messy to deal with compared to your black and greywater RV tanks.

If you follow the process correctly, you will find that your RV will always have clean water in its freshwater tanks. However, before you begin cleaning your tanks, you need to have all of the necessary supplies ready. Here is what you should have for the process:

  • Bleach
  • Funnel
  • Measuring cup
  • Clean water supply

The most important thing that you can do to ensure that your fresh water tank is sanitized is to have clean potable water, to begin with. If you end up filling up your tanks with poor-quality water from the start, then you can expect your water supply to get contaminated very quickly.

If you are going to use a fresh water hose connected to your home’s outdoor water outlet, confirm that it is a clean water source first. We also recommend that you never use undiluted bleach for the process, as it can damage plumbing, gaskets, and all sorts of different components of your RV. Let’s dive into the process of cleaning and sanitizing RV freshwater tanks.

Turn Off Your RV Water Heater

This is the first mistake that so many people tend to make when cleaning and sanitizing their freshwater tanks. You should absolutely turn off your RV’s hot water heater before you begin doing anything else.

Leaving your hot water heater on with no fluid in the system can result in some serious damage being done to it. You need to turn it off and give it around 15 or so to cool before beginning the cleaning process.

Drain Freshwater

Once your RV’s hot water heater has cooled down, you can drain the system. If your RV has a built-in water pump, it would be wise to utilize it in this situation - especially if you have an older model RV or have not drained your freshwater in a long time.

Your water pump is going to encourage optimum flow for all fluids to come out of your RV. However, once all of the water has drained, switch off your water pump to not damage it.

Bypass Water Heater & Appliances

Before you begin pouring bleach into the system, you first want to ensure that this harmful chemical is not going to reach any of your RV components where it might cause harm to your vehicle.

To start, bypass your RV hot water tank to prevent any beach from entering it. Cleaning and sanitizing your water heater is not part of the process and does not need to be done nearly as often as your freshwater tank.

Next, you will want to shut off any other appliances that you have in your RV that may be connected to your hot and cold water lines. This would include things like ice makers and dishwashers. Lastly, if your RV does not have a bypass switch to prevent fluids from reaching your water filters, you will want to remove them as well, as bleach is going to damage them.

Add Bleach to Freshwater Tank

With your freshwater supply drained, water heater bypassed, and all components secured - you can add bleach into your system.

First, identify how large your RV fresh water tank is by determining exactly how many gallons go into it. You want to add the right amount of bleach as too much or too little is not going to do your RV any good. Depending on the type of RV that you own, this number can fluctuate quite a lot.

Larger RVs like Class As will have water tanks that are generally 75 to 100 gallons. Class Bs have considerably smaller freshwater tanks and will store 20 to 40 gallons. Whereas Class Cs typically have 35 to 60-gallon tanks.

Generally speaking, you want to add about 2.5 fluid ounces of bleach for every 20 gallons of fresh water. If you have got a larger freshwater tank, add bleach as needed. As we mentioned above, you do not want to pour bleach directly inside of your RV fresh water tank, as this can damage some components of your fluid system.

Take a gallon of water in a bucket and pour your bleach into their first. If you have got a huge RV and fresh water tank, you may want to separate this into two different loads to properly dilute the bleach. With your diluted bleach in hand, place a funnel over your RV fresh water tank opening and pour it inside of the system to let the sanitization process begin.

Fill Water Tank

Next, fill up your freshwater tank. Make sure that you are doing this from a clean water source, as it can be counterproductive otherwise - most municipal water sources should be fine.

You want to fill the tank to its capacity to have the most effective cleaning and sanitization effect. Once your tank is full, you can switch on your freshwater filter to give your system optimum flow so that it reaches each part of your RV.

Then you will want to encourage this further by opening up all of your RV’s freshwater water outputs. This will include your shower water, kitchen sink, as well as any additional sinks that your RV may have. You want to do this for both your hot and cold water faucets. Let the water flow until you can smell bleach in every water output so that you know that it has thoroughly gone through everything.

After the bleach has reached all of your RV’s water outputs, you can then turn off each one to let the water sit in the system. You want to give the bleached water some time to kill all of the bacteria inside of your freshwater tank and system. This will normally take around 4 or 5 hours. However, overexposing your system to bleach is not good for it either, which is why you want to try to keep the water in there for this amount of time and not much longer - with 12 hours being the maximum.

Flush Freshwater System

If you have let your bleached water sit for a while, it is safe to say that you have probably killed all of the bacteria inside of your system. You can then continue the process by draining your entire freshwater tank and system to get rid of the bleached water.

However, you are going to find that there is still a considerable amount of bleach residue that is going to linger inside of your RV’s fresh water system. This is not something that you want to consume as it can be harmful and dangerous to your health, which is why you want to flush your system again with fresh potable water.

Fill up your RV’s tank (again) and engage your freshwater pump to encourage the water to flow through the entire system. Once you have let it run for a short while, drain everything again. Your RV should be fully clean and most of the bleach will be out at this point. However, we always recommend repeating this process at least 2 or 3 times, as it can be quite difficult to get all of the bleach out on the first flush.

Continue the process of flushing your RV’s fresh water system until you can no longer smell bleach coming out when your drain the water. At this point, the bleach will have diluted enough to where it will be pretty much harmless. With that being said, if you hit the road and find that your RV’s water tastes a bit like bleach, you may want to consider giving it another flush to seal the deal.


Anthony Day

Anthony Day

Hi, my name is Anthony, and RVs are what I'm passionate about. I bought my first RV when I was 21, and I've been hooked ever since. I'll guide you on how they work, how they can be used in different environments, and how they fit into our everyday lives.

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