Locate and identify the water pump

Water pumps are the heart of the water system and can be either hand operated, manual electric or demand pumps. They are supplied by several different manufactures.

Hand water pumps are used on small units such as folding camping trailers and truck campers. With hand pumps water is drawn from the storage tank by a simple pumping motion.

Hand/manual electrical pumps offer two modes of operation. The hand pump action works like a normal hand pump. The manual electric mode functions by positioning the handle differently which activates a small electric pump.

Demand pumps automatically turn on when a faucet is opened. When the pump is on, but no water is being drawn, the pump runs only briefly to pressurize the lines. When the line pressure reaches about 40 psi, the motor shuts off until a fixture is opened. This momentarily lowers the pressure at the pump which activates the pump motor.

Water pumps work most efficiently when they are mounted near the water tank and at same level as the bottom of the tank, however many pumps are mounted above the fresh water tank. Water pumps can “push” better than they can “pull”, but most are capable of self-priming if they are above the water level of the tank.

Locate and operate toilet

Four types of toilets can be found in RVs: mechanical seal, house type flush toilets, recirculating, and portable. Mechanical seal toilets are the most common toilets used in recreation vehicles. This toilet is required to be connected directly to the body waste holding tank. The flushing mechanism for this type of toilet is either a hand-operated lever or a foot pedal which operates a slide type valve. Mechanical seal toilets do not have a separate flushing tank as found on home toilets. Water is fed directly from the RV’s water system to the toilet.

The house-type toilet is permanently mounted in the RV and flushes using water from the fresh-water system, similar to the toilet in conventional housing. These toilets are not permitted to be connected to a wastewater holding tank because of the high volume of water involved with each flush. Instead, these toilets—often called water seal toilets—are designed to connect directly to a park’s inground sewer system.

Recirculating toilets are self contained and do not require any pressurized water source, either from the city water connection or from the potable water storage tank. To use a recirculating toilet, it must be “charged” with a supply of potable water poured into the toilet from an external source. A recirculating toilet uses a 12 VDC pump to recirculate the water charge for flushing. The liquid is separated from the solid wastes and used to flush the toilet. The recirculating toilet is self-contained, although a holding tank can be installed to increase capacity. However, once the toilet’s contents are emptied into the holding tank, the toilet must be recharged with potable water to properly function.

Portable toilets are most often used in smaller recreation vehicles that are not equipped with drainage systems. Typical RVs using portable toilets are folding camper trailers and truck campers. Potable water is introduced into the freshwater tank, or the upper section of the toilet and only used to flush the bowl. The lower tank, or waste holding tank, will need some chemical to accelerate solid disintegration, sanitize, and prevent excessive odors. A foot operated pedal or a hand pulled gate valve opens the passage from the toilet bowl to the holding tank.

Demonstrate how to drain a water heater

The water heater has a drain fitting on the exterior portion at the bottom of the tank for flushing and draining purposes. The drain fitting may be a steel plug or a plastic plug. The drain fitting is a female pipe thread fitting so care must be taken not to cross thread the fitting when reinstalling the plug. Use the proper pipe sealants. The drain is accessed through the exterior access door.

Demonstrate how to drain a water storage tank

Two types of water storage tanks for potable water are used in RV's, non-pressure and pressure tanks. Non-pressurized storage tanks are by far the most common type used. These tanks are usually made from lightweight and durable plastic. Most tanks found in RVs today are made of polyethylene plastic although ABS tanks are also available.

Water storage tanks must be equipped with a low point drain to allow the tank to be completely emptied by gravity. This is helpful when sanitizing or winterizing the water distribution system. This drain may be through the side wall with a draincock, or it may be through the floor of the coach. If the drain goes through the floor, the valve may be outside with the drain hose, it may be inside, usually at the tank drain outlet, or above the floor just before the drain line drops through the floor.

Demonstrate how to drain a waste water system

Waste water holding tanks are used to collect the waste water of the RV and safely store it on board until it can be emptied into an in-ground sewer system. RVs manufactured today typically have two waste holding tanks. The liquid waste holding tank is commonly called a “gray water” holding tank and collects the water coming from the shower and faucets of the system. The body waste holding tank is commonly called the “black water” holding tank and collects the wastewater from the toilet(s).

Holding tanks should be over half full for proper dumping. This means that at times water may need to added to the tank in order to effectively dump the holding tank. By adding water to the holding tank, remaining solids will be broken down further and carried through the drain with the force of the weight of the additional water.

Always dump the black water holding tank first. This allows the gray water tank to “rinse” the hose later. To dump the black water holding tank, connect the 3-inch flexible drain hose to the dumping outlet. The RV drain outlet will be equipped with a bayanet type hose coupling that locks by turning clockwise. Attach the other end to the dumping station or campsite hookup. Make sure that the gray water fullway termination valve is closed before dumping. This will prevent the black water waste from backing up into the gray water holding tank while it is being drained. Pull out the termination valve handle fully and let the holding tank drain.

Upon completion of the black water dumping, the gray water tank is dumped in the same manner. The slide valve for the black water holding tank is closed and the termination slide valve for the gray water tank is opened. Some systems have separate termination valves for black and grey water. After dumping the black water, the sewer hose is then moved to the grey water valve to empty the gray water tank and rinse the hose.