Tiffin Motorhomes Allegro Bus 2011, Owner'S Manual

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P L U M B I N G & B A T H F I X T U R E S
11-9
P-Traps
Each of the sink drains, the shower drain, and the washing-machine drain (if so equipped) has a water trap (P-
trap) to prevent holding-tank odors from entering the motor home. These traps must have water in them to
trap odors. When the vehicle is in motion, the water may splash out of the sink and shower drains. When the
motor home is stored, the water may evaporate from these traps allowing odors to enter the motor home. If
this occurs, run water from the faucet into the drain, thus allowing water to fill the traps again. A good practice
would be to run a little water into these drains on a monthly basis.
Black-Water Holding Tank
The “black water” (i.e., sewage) holding tank is located directly beneath the toilet. Before using the toilet, you
will need to treat the tank with water that is mixed with an odor-controlling chemical. These chemicals are
readily available at any RV supply store. Be careful not to spill the chemicals on your hands, clothing, or the
carpet because such may cause a permanent stain. Pull the toilet levers forward to allow the chemicals to mix
with the toilet water. Continue pulling the toilet levers until a depth of at least one inch of solution is directly
under the toilet. Release the levers and the waste tank is now ready for use.
Caution
Use only approved RV odor-controlling chemicals in the holding tanks. Products
containing ammonia and petroleum will damage the ABS plastic holding tanks and
seals.
Gray-Water Holding Tank
The gray-water holding tank is located in the underbelly of the vehicle. It is primarily used for the drainage
from the kitchen and bath sinks and the shower.
Wastewater Disposal
Both of the holding tanks terminate in a valve arrangement
that permits draining each tank separately or together (Figure
11-13). It is recommended to drain the black-water tank first
before draining the gray-water tank. This procedure permits
the water from the gray tank to wash the black-water residue
from the drain lines and hose. The valves that open to release
the water are called gate valves.
The blade that closed the opening in the sewer drainpipes is
connected to the T-handle to release contents of the tank(s)
when pulled. The sewer line must be securely capped
Figure 11-13. Sanitation Compartment Containing Holding
Tank Drains and Flexible Drain Hose