Whether you’re a first-time RVer or a seasoned veteran, it’s a good idea to understand your RV plumbing system. By knowing how your system works, you’ll be able to identify potential problems and repair them before you rack up thousands of dollars in repair costs. (Plus, winterizing and de-winterizing your RV is also much easier when you understand how the different aspects of your plumbing system work).
The good news is that you don’t have to be a licensed plumber to understand RV plumbing systems. While these systems function similarly to a residential plumbing system, they operate on a much smaller scale and with fewer working parts (which means fewer parts and concepts to study).
Part 1: Understanding RV Plumbing Systems
The key to understanding your RV’s plumbing system is to understand the different parts that compose it. Here’s a quick rundown of the different entities within the system.
Understanding the Fresh Water System Tank and Supply
First up, you have our fresh water supply. You can use fresh water in your RV in one of two ways.
- Fill the freshwater tank on your RV and use it as your water supply.
- Connect a water hose from the campground’s freshwater supply spigot to the City Water Connection on the side of your RV. Once the hose is connected and the water is turned on, you can use all the freshwater you desire.
Water Pressure Regulation 101
Rather than connecting from a water spigot directly to your RV, however, it’s important to use a water pressure regulator as the go-between. You see, the water pressure at a campground may be too high for your plumbing pipes to handle. If you connect to running water without a pressure regulator, there’s a good chance that a pipe will burst.
A water pressure regulator helps control and maintain a consistent water pressure entering the RV, safeguarding the plumbing system against high pressures.
Intro to Plumbing Pipes
As with a house or business, water flows throughout your RV and eventually exits it via a series of pipes and drains. Water travels to your showers, toilets, and sinks via hot and cold water pipes, then flows down a series of drain pipes into holding tanks beneath your RV.
Note that each plumbing appliance is also connected to a vent to prevent foul odors and other issues.
Intro to the Water Pump
Most RVs are also equipped with a water pump, which forces water through the plumbing system to various fixtures and appliances. RV water pumps operate using electricity and are necessary when gravity alone isn’t enough to get water where it needs to go.
A Guide to the Grey Water Tank
The grey water tank on your RV serves the same purpose as a septic tank on a house. Any water you use at your bathroom sink, kitchen sink, or shower goes down the drain and flows into the grey water tank. Once the tank fills up to a certain point, you’ll need to dump it manually, but more on that in a minute.
A Guide to the Black Water Tank
While the grey water tank is reserved for drainage from your sinks and showers, the black water storage tank on RVs holds all toilet waste. This means that anytime you flush your RV toilet, the water, waste, and toilet paper run down the drain and into the black water tank, which is separate from the grey tank.
Waste Management and Dumping 101
Once your sewer system, aka, your black and grey tanks, fill up, you will need to drain them, and here’s how:
- Connect one end of your flexible sewer hose to the dumping port on your RV.
- Connect the other end to the sewer hookup at your campground or dump station.
- One at a time, open the drain ports on your RV to dispose of waste.
- Start with the black tank, proceed to the grey water tanks, and leave them open until they are empty.
Part 2: Hot Water Heaters in RVs
Depending on how new your RV is, it will also most likely have a water heater. Although they’re much smaller and look different than residential ones, RV water heaters serve the same purpose. Cold water flows into the holding tank, where a heating element heats the water up and sends it to your showers and sinks.
How to Choose the Right Heater
If you have an older RV that was built without a water heater, you can always install one after the fact. Here are some of the best RV water heaters on the market:
When choosing your water heater, it’s important to note that there are electric, propane, and hybrid options. It’s important to choose the right type of water heater based on your power supply or choose a hybrid one if you want the option to power it with either propane or electric.
How to Maintain Your Hot Water Heater
If you have a water heater installed in your RV, it’s important to protect and maintain it. Here are a few tips and tricks to ensure your water heater lasts for years to come:
- At the end of every camping season, drain the water heater and inspect the heating elements for corrosion. If the anode is too corroded, replace it with a new one.
- Periodically throughout the camping season, flush the water heater using white vinegar. This will help remove hard minerals that inevitably enter the tank and stick to the sides and bottom.
Part 3: Essential RV Plumbing Accessories
In addition to each of the plumbing fixtures and appliances pre-installed on your RV, there are a few extra ones you should consider adding.
Water Filter
Campground water is notorious for being filthy and full of dirt and other contaminants. Installing a water filter somewhere between the water supply and your RV will keep these contaminants from getting into your water system.
Water Softener
While water filters are effective at removing solids in your water supply, they can’t remove calcium, magnesium, and other minerals that make water hard. Therefore, it’s a good idea to install a portable or permanent water softener to make your water cleaner, softer, and safer.
Sewer Hose and Fittings
Most RVs come with an industry-standard sewer hose. However, it’s often short and cheaply made, which means it will likely give out or spring a leak in short order.
Therefore, it’s a good idea to upgrade to a high-quality sewer hose and fittings. This includes at least one coupling and elbow, as well as a sewer drain hose extension for situations when your hose is too short to reach from the RV to the campgrounds’ sewer port.
Part 4: RV Plumbing Maintenance and Troubleshooting
Just like the plumbing system in your home, your RV plumbing system needs regular maintenance to keep it working smoothly. Here are a few maintenance and troubleshooting tips and tricks to ensure your plumbing system is working at peak performance!
- Always winterize your RV at the end of the season to prevent burst pipes.
- If you plan to leave your RV for 12 hours or more at a time, turn off the water supply.
- Always use a water pressure regulator, water filter, and water softener to ensure clean, safe, and usable water.
- Flush your black tank periodically to prevent clogs and blockages.
- Dump TST liquid into your gray water tank and freshwater tank once per month to prevent odors.
- Be on the lookout for water leaks and fix them the second you spot them! The Fit RV is a great YouTube channel to follow for instructions on fixing plumbing problems yourself.
Final Thoughts
There’s a lot that goes into a properly functioning RV plumbing system. As such, there are also numerous problems that can pop up if you don’t maintain it properly. In addition to problems that can happen while you’re using your RV, there are also issues that can occur because of improper RV storage.
To ensure your RV is stored safely and securely, consider using Neighbor, a peer-to-peer storage marketplace. Reserving your storage space through Neighbor will help ensure your RV plumbing system is intact and ready to go for next year.
