Thor Motor Coach 2009 Mandalay, Owner'S Manual

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MANDALAY
The waste water system in the motorhome can be described as two separate systems. A gray
water system that consists of drain lines and holding tank for waste water from the sink and tub,
and a black water system which includes the holding tank and drain for toilet waste.
In some cases the bathroom lavatory may drain into the black tank. Each system is self
contained and allows disposal of waste at designated dump stations for your convenience.
Components of the gray water system have drain traps and both tanks are vented to
equalize air pressure and disperse odors caused by drain water and waste. Sometimes, the
rocking movement of the motorhome while driving may empty the drain traps of their water and
allow the odors of the gray water tank to come into the coach. Residue in the drain water lines
can also produce odors. To combat gray water holding tank odors, an approved deodorizing
agent should be used. An agent that dissolves grease and fats and contains a detergent will
help keep tank drain lines clean and free-flowing.
Both holding tanks are located under the bathroom area. The drain valves are located in the
systems compartment on the driver side of the motorhome. Each tank has a separate drain line
and dump valve which permits dumping tanks individually or together. Each tank should be
emptied often at a dump station designated for this purpose. Most national, state, and private
campgrounds have dumping facilities. Many have hookups on the campsite, while some have
portable dump collectors. Many service stations, particularly along interstate highways, also
have these facilities. Most campground directories list dumping station locations across the
nation.
If possible, dump holding tanks before a trip to reduce the gross weight of the vehicle.
Enough water should be kept in the black water tank to cover the bottom to prevent
hardening of any residue that may remain.
Do not dump black water tank until it reaches ¾ full. This practice makes sure that enough
water is in the tank to flush all waste into sewer lines. If necessary, fill tank to the ¾ mark with
additional water before draining.
Never put anything into the holding tanks other than normal drain water, waste, and
biodegradable products. Paper wrappers, gum, cigarettes, etc., no matter how small they might
be, should never be placed into either the gray or black tanks.
NOTE: It is important to note that harmful and toxic materials can accumulate if the holding
tanks are not regularly drained and thoroughly rinsed. It is also important to use holding tank
deodorizing and cleaning agents in the waste water tanks to reduce odors and keep the lines
open and free-flowing.
NOTE: Always remember to clean up the dumpsite before leaving. NEVER empty your holding
tanks directly on the ground, a roadway, river or stream. DO NOT POLLUTE.
10-5
WATER SYSTEMS
WASTE WATER SYSTEM
Holding Tanks