A variety of components all work together to make up the RV plumbing system. Routine maintenance and a few tricks of the trade will help guarantee you get maximum benefit from your coach’s combined on-board water systems.

Plumbing pipes in a recreational vehicle resemble those used in home construction, but differ in draining methods. Holding tanks store wastewater until it is flushed away through a sewer outlet. Carefully monitoring how much room is left in those tanks is always a good idea, because what may appear to be a clogged drain could actually signal a full holding tank.

A monitor panel is located inside the coach, or sometimes a panel can be located outside the coach in the water service center. The monitor panel communicates with sensors in the holding tanks to measure current tank levels. Solids built up around the sensors in the holding tanks can create false readings. When the freshwater tank is filled and waste tanks are empty, reference the panel to confirm accurate readings. As the tanks are being used, frequently check the panel to be sure the information is adjusting as water is used.

For safety’s sake, it may seem to make more sense to simply bypass the tanks when hooked to shore service, and in fact, this does work when it comes to the fresh and gray water holding tanks. However, keeping the valve open on the black holding tank eliminates liquids that the tank requires in order to keep solids from building up around the tank sensors, or from clogging the tank.

Before dumping the black tank, fill the gray tank to a third of its capacity. Then use that water to flush the hose after dumping the black tank. Empty the black holding tank when it reaches one-half to three-quarters full. Prior to removing the cap, examine the slide valve to ensure the valve is secure and did not come open while the coach was driving down the road.

Solids built up around the sensors in the holding tanks can create false readings. When the freshwater tank is filled and waste tanks are empty, reference the panel to confirm accurate readings.

Always use a good quality sewer hose to empty the tank. As hoses age, they may fail to compress, or may develop small holes. Never risk spillage by attempting to repair a damaged hose. When the sewer hose becomes worn, replace it with a new hose. Confirm that the clamp on the black water sewage hose is secure before you evacuate the tank. When lining up the hose to dump the tank, a slight slope is fine, but beware of slopes with more than a slight incline, as that can cause the liquids in the tank to drain before they’ve had time to flush out solids.

Once the black tank is evacuated, add a few gallons of fresh water and an odor control chemical. Odor control is a necessity in maintaining the tanks. Specially designed chemicals for the black tank are available at camping supply outlets and should be added after the tank is emptied and the valve is again closed. Follow the recommended amounts listed on the product label. In hot weather, it may be necessary to add additional odor control treatment to the tank.

Take steps to reduce the risk of clogs at the toilet. Add water before each use to aid in flushing. Use only paper specially designed for RV use, paper that will quickly dissolve. Avoid flushing foreign items down the toilet, such as tissue paper, feminine hygiene products or cotton swabs. Learn how to operate the manual override valve to stop the water flow in the event the black tank becomes full. This may involve going outside to the shore connection and turning off the water. Some newer toilet models are designed to stop flushing when the system senses a full black holding tank.

To help prevent odor escaping from the gray tank, run water down the drain to fill the P-trap, or elbow. This is especially important when the coach is in storage, and water in the pipes has evaporated. Treating the gray tank with an odor control chemical is usually not required, however, food particles trapped in the drainpipes may build up and create an odor that can be eliminated when chemicals are poured down the drain. If it is necessary to add odor control chemicals to the pipes, pour equal amounts into each drain and allow the substance to sit overnight. Prevent food buildup in the plumbing system by thoroughly removing food from dishes and utensils before washing them in the sink.

Potable water hoses should be stored with both ends screwed together to prevent insects and dirt from entering the hose when not in use.

To disinfect the freshwater tank, fill the tank and add one cup of household bleach. Remove filters, engage the water pump and run the treated water through all faucets, including the shower. Let the solution stand for four hours and then flush the system using fresh water only.

When finished cleaning the tank, reinstall the filters. Filters are designed to trap particles in the water. Filters are rated in microns — the smaller the micron, the greater the amount of sediment filtered. Follow the recommended filter replacement schedule to help ensure a quality water supply.

Another way to help the freshwater supply remain clean is by filling the tank using a clean hose. Potable water hoses should be stored with both ends screwed together to prevent insects and dirt from entering the hose when not in use. Replace potable freshwater hoses when they appear worn or damaged.

To properly fill the freshwater tank, park on a flat level surface and attach the potable water hose to the tank and the ground water supply connection. Do not attempt to hurry the job along by cranking the shore service to full force. Too much pressure can force water out the overflow valve and create a siphoning effect. For best results, use a moderate measure of force when filling the tank, stay nearby to monitor the tank level, and as soon as water appears at the overflow valve, quickly turn off the faucet.

All holding tank activity begins with the faucets and routine care should be given to these components. Faucet drips usually occur when a handle is not fully turned off. Frequent cycling of the water pump when there is no requirement for water may indicate a dripping faucet. Make a full inspection of all faucet handles, including the shower faucet in the outside service center. Seals in the faucet assembly may wear out over time causing a faucet to drip. Before replacing a seal, be sure to turn off the water supply and disengage the water pump. Faucets can be easily scratched by screwdrivers and pliers, so use caution and protect the faucet assembly when taking it apart to replace worn parts. An aerator screen is usually installed at the opening of each faucet to trap minerals that may contaminate the water. Occasionally unscrew the screen by hand and clean away contaminates using a brush.

Water pressure varies from campground to campground, so a water pressure regulator should always be used to protect the RV plumbing system. Attach the regulator between the potable water hose and the shore service faucet. Don’t forget to remove the regulator when it’s time to go.

Whether you’re hooked to shore services or dry camping, water system efficiency for your coach is critical. Stay within the parameters of what the system is designed to do and you’ll surely benefit from the pleasing conveniences of RV plumbing.