How to Refill the RV’s Fresh Water Tank

How to Refill the RV's Fresh Water TankSteps for Refilling Your RV's Fresh Water Tank:

  • Locate your fresh water connection.
  • Make sure that all tanks, hoses, and connections are clean and free of debris.
  • Add water from an approved hookup or source.

Following the proper procedures for refilling your water tank is very important. Keep reading for more details on how to to make sure that your refill is safe and sanitary!

Locate Your Fresh Water Connection

The first step to filling your fresh water tanks is to locate your fresh water connection. This is usually located near the rear of your rig, either behind a master panel or with a screw top lid covering an inverted spout. With a newer RV, you often have the option of utilizing a valve that can divert water from the city water input into your fresh water tank. Check your owner’s manual for specifics about your particular model.

Safety Measures

Let’s take a moment to consider a couple of important safety measures. When adding water to your rig, whether through the city water port or into your freshwater tank, it is important to use equipment with FDA specific materials for freshwater use.

Always use potable water and consider an external in-line filter, even if your rig has an internal filter. This extra layer of protection helps to keep silt and debris out of your tanks, saving you money in the long run, for a small amount up front. Before you add water, make sure your tank is clean.

Despite the name, the fresh water tank is a breeding ground for bacteria and requires proper disinfecting before use, and in between uses. There are specific products on the market for this, or you can use one of the many internet suggestions.

It is important to always feel confident that your water source, pipes, hoses, and tanks are fresh and clean!

Just Add Water

Now that you have located your freshwater port and you have a designated fresh water hose, the next step is to just add water! If you are at home or a campground where city water is available, you can either fill straight into the fresh water tank or connect to the city water hookup port and divert using your valve.

Y-Valves and Pressure Regulators

Optional additions to the process are the use of Y-valves and pressure regulators. These are highly recommended.

The Y-valve makes it easy to have a fresh water hose and your tank cleansing hose hooked up simultaneously, and the ability to turn one on or off without disconnecting.

The pressure regulator is very important when using campground facility city water. The plumbing is highly irregular and can cause major damage to the inside of your rig! Again, this product can end up saving you money in the long run.

Alternative Water Sources

Many campgrounds, like State Parks, do not have full hookups. If this is the case they may have a spigot that is available for potable water. This is usually this is located at the dump station, but can also be in an area between campsites. You should be able to connect your fresh water hose directly to the spigot. Be sure to use your filter and pressure regulator.

There are times when a little more creativity is involved, and it is a good idea to always have a large portable water tank with you if you plan on being away from a water source. Using a portable tank can be tricky, as they can weigh nearly a hundred pounds when full and will need to be hoisted up to be able to dump into the tank. Luckily, there are products available to pump the water into your tank if you aren’t up for the extra workout.

Always use Approved Water Sources

Do not use water from unapproved sources, such as your neighbor's house, the spigot you spotted outside of a major convenience store, or a nearby river. There are, however, some places that will allow you to use their water. Always ask permission and be courteous, allowing RVers to continue having the reputation as the awesome people we are!

Consider Your Needs

As you are filling up, it is important to consider your needs. Are you planning on dry camping/boondocking? Are you going to be traveling with full tanks?

Water is heavy and can add nearly 10lbs per gallon of extra weight. With a Class A RV holding up to 100 gallons, that’s an extra 1,000 lbs of weight! This can put a strain on your gas mileage and/or put you over your GVWR (Gross Vehicle Weight Rating) which can open the door to a terrible list of problems from broken axles to insurance companies not covering accidents!

If you aren’t traveling far and will be in need of utilizing the most of your RVs capabilities, you can turn on your fresh water pump and add water to the water heater, while filling up, to gain an extra 5-10 gallons.

Don't Fill Up Until Necessary

Most resources, however, recommend not traveling far with full tanks unless you won't have water hookups available to you. If you are going to camp at the local State Park for the Weekend, you can probably wait to fill up until you get there. If you are dry camping/boondocking in a location where you won’t have water available and need to be self-contained, filling up with water before parking is a necessity.

Be Conservative

In many parts of the dry side of country, you will see signs that say, “Water Is Life” which is absolutely true while RVing! Water for dishes, showering, laundry, toilets, and handwashing, as well as drinking, can use up your fresh water reserves quickly! Just one shower can use 30-35 gallons! Conservation is paramount, and it doesn’t hurt to keep a few extra gallons with you via jugs, containers, or bladders.

Proper Disposal

We’ve covered finding your connections, using proper gear, always using fresh potable water and clean tanks, optional (but highly recommended!) additional tools, and assessing your personal RV trip water needs. Now, let’s talk about where all that water goes.

After using water in your RV it will go into either the grey tank or the black tank. The grey tank comes from all of your sinks and the shower (or bathtub if your rig is a little extra awesome!). This grey water is soapy and dirty. The black tank collects toilet waste.

When emptying your rig, it is a good idea to do the blackwater tank first, and greywater tank last, as it will help to wash out the hose. Always use a separate hose, not your fresh water hose, for flushing out the tanks. You really don’t want to take chances with a tank under pressure pushing solids into your clean water hose. Many people designate the hoses either by color (white for fresh water, orange for flushing) or write on them with a permanent marker.

Don't Drain and Drive

It is considered bad etiquette to open your tank valves, including the fresh water tank, and drain it while driving. If you want to empty your fresh water tank before packing up, turn on the pump and run it into your sink or toilet. The extra water will help dilute the tanks and clean them out more thoroughly.

Adventure Awaits!

RVing is always an adventure packed full of exciting opportunities and incredible vistas. It gives us the courage to take chances on new locations, vacations, and expectations. The one thing you shouldn’t leave to chance is making sure you have fresh water available, and the know-how to keep it that way.

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  1. I think fill freshwater tank is very important to have a good journey. I read your post and I think it has good and useful content for me. I will use your way to do it on my next journey. Thanks so much!!

  2. Thanks for replying, I very happy when you like my comment. By the way, I used your way to fill freshwater tank, it worked well and I satisfied with it. I am gonna following more of your posts, please update more about posts like this post.

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