RV Water System Explained

In this guide we walk you through everything you need to know on your RV water system, common RV water system troubleshooting fixes and more. 

RV Fresh Water Tank Care

Question: Is there something we should add to the water in our holding tank for clean water? It is starting to have a musty smell.
Answer: You should make sure you sanitize your fresh water tank on a periodic basis. Please see our page on this subject at www.your-rv-lifestyle.com/sanitize-rv/.

If you are referring to your gray water tank, we just make sure we flush the tank thoroughly with clean water every few times we empty it. We have not found a need for holding tank additives for the grey tank.

Also, you should keep the valves closed on both gray and black water tanks. Keeping them closed helps prevent build up of waste deposits in the bottom of the tanks and helps prevent the seals from drying out. So you will help prolong the longevity of your tanks.

Also, if you leave the valves open, you will suck odors right through the open valves into your rig and the neighborhood. Keep them closed and only open them when you need to empty the tanks.

Where to get Fresh Water

Question: I am just starting to look into the prospect of fulltime RVing.

I have never owned an RV. I’ve seen questions and answers online regarding filling and sanitizing the fresh water tank and so on, but wonder where you can fill the tank with water. H2O is expensive in many places – so who will allow you to fill a tank if you are not in an RV park?

Answer: A few places to consider are rest stops, some gas stations/truck stops, propane stations, state and national parks. You will likely encounter varying degrees of success.

Some RV parks also have a dump station and water supply that traveling RVers can use, even though they are not staying in the campground but usually for a fee.

Be careful that you get potable water. You may find water at a dump station, but it may be intended for rinsing off sewer hoses and not be potable. Look for signs and be careful.

You should carry your own hose (or hoses in different lengths) to fill up your fresh water tank. Use hoses designed for drinking water (not just a garden hose) and do not use this hose for anything else but filling your fresh water tank. You need to keep this hose sanitary, stored separate from other hoses or supplies.

Always let the water run for a bit at the spigot of a fresh water source before connecting the hose.

You may also want to carry a small spray bottle with some bleach in it to sanitize the hose bibb before using it, as a safety measure. An ounce of prevention.

And consider carrying an adapter to connect to spigots that do not have a hose bibb, as might be the case in some public places.

Here is a handy website that has lots of listing for dump stations, showing whether water is available: www.sanidumps.com .

Overfilling Fresh Water Tank

Question: City water is overfilling the fresh water tank. Why is this happening and what should I do to fix it?

Answer: With this limited information, it is difficult to offer much advice. Your RV should have a valve that you open to fill the tank and close when the tank is full. If you have closed the valve and the tank is overfilling, then it seems you have a bad valve that needs to be replaced or repaired.

Comment 1: We assume that your RV does not have a city water connection that has a diverter valve and that you are filling using the gravity feed to fill your tank. If that is the case, I would look on-line for something you can attach a hose to and hook the end into the gravity feed opening. Or, you might be able to make something that looks like a goose neck that is small enough to fit in the opening and if you get creative you could also add a shutoff valve.

Comment 2: I would not connect the two ends together unless you are going to use the hose within a day or two. I too would be concerned about stuff growing in the hose. If you do want to connect the hose ends then I would add a table spoon or two of bleach. Make sure you don’t leave the ends connected for a long time, the bleach will corrode the connections after several months.

Comment 3: It takes our little rv forever to fill with water. Is there an adapter to attach to the hose to fit better in the water hole on side of RV?

Comment 4: When I remove my white potable hose and drain the excess water, is it okay to connect the male & female ends together or should I wait until the hose is completely dry to avoid any mold or stagnant water ?

Comment 5: Your house water tank uses an electric pump, which contains a back-flow preventer so that pressure from the city water hookup does not go into the house fresh water tank and overflow it as yours does. Your pump’s back flow preventer is apparently bad or jammed open with debris.

You can repair the pump, replace the pump, or add an additional in-line back flow preventer, or simply use a manual valve between the city water and the house water.

RV Water Pots

Question: I have a Coachman Catalina Lite and have question. I have potable water and city water ports on the side of my trailer, and was wondering if I fill both with tap water prior to camping?

Answer Your potable water and city water ports fill the same fresh water tank. The reason you have two ports is that one is for a gravity fill (potable water) and the other is for pressurized water (city water) like from a hose
attached to the potable water hookup at a campsite.

What you called the potable water port is used to pour water into the fresh water tank from jug or some other container. So that if you forget to fill the fresh water tank you can stop at a store and buy however number of gallons you need to fill the fresh water tank through the fresh water fill.

The other port or city water port has a female hose connection to which you attach a potable water hose and connect it to a potable water supply like a spigot/faucet that supplies water under pressure. Be sure to use a potable water hose – not a garden hose to fill your fresh water tank. You will be using the fresh water for food preparation, washing, brushing teeth and possibly drinking (if you have it filtered sufficiently for your preferences).

You may also want to see our page about sanitizing the fresh water system at http://www.your-rv-lifestyle.com/sanitize-rv/