VACUUM WASTE SYSTEM -VACUUM BLOWER AND FILTER
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Jan 05/2002
VACUUM WASTE SYSTEM -VACUUM BLOWER BAROMETRIC SWITCH
Purpose
The vacuum blower barometric switch de-energizes the vacuum blower when the airplane is above 16,000 feet.
Physical Description
The switch is a microswitch. The microswitch has a capsule and an electrical connector.
Location
Two vacuum blower barometric switches are aft of the bulkhead near the floor on the right side.
Functional Description
The capsule monitors the air pressure outside of the airplane. As the pressure outside decreases the capsule expands. This opens the blower circuit.
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Jan 05/2002
VACUUM WASTE SYSTEM -VACUUM BLOWER BAROMETRIC SWITCH
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Jan 05/2002
VACUUM WASTE SYSTEM -VACUUM CHECK VALVE
Purpose
The vacuum check valve prevents reverse air flow through the bypass line when the blower is on.
Physical Description
The check valve is a flapper-type valve.
Location
The check valve is in the aft cargo compartment on the left side. The valve is in the blower bypass line that vents overboard. The valve is aft of the blowers and outboard of the forward waste tank.
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D633W101-BEJ Jan 05/2002
777 AIRCRAFT MAINTENANCE MANUAL
VACUUM WASTE SYSTEM -VACUUM CHECK VALVE
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ May 05/2002
VACUUM WASTE SYSTEM -LIQUID SEPARATOR
Purpose
The liquid separator removes moisture and waste particles from the waste tank air before venting the air overboard.
Physical Description
The liquid separator has these parts:
*
Demister mesh
*
Outer canister
*
Inner bowl canister (not shown)
Location
The liquid separator is at the top of each waste tank.
Functional Description
Vents on the outer canister makes sure the air goes in a circular path when air goes into the canister. Centrifugal force removes moisture from the air. The moisture drains out the bottom of the liquid separator. The air then goes into the inner canister and through a demister mesh. The demister mesh removes any material still in the air. The air then goes to the overboard vent line.
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Sep 05/2002
777 AIRCRAFT MAINTENANCE MANUAL
VACUUM WASTE SYSTEM -LIQUID SEPARATOR
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Jan 05/2002
VACUUM WASTE SYSTEM -WASTE TANK DRAIN BALL-VALVE AND CONTROL CABLE
Purpose
The waste tank drain ball-valve and control cable permit the waste tank to drain.
Physical Description
The waste tank drain ball-valve has these parts:
*
Housing
*
Actuation lever
*
Limit switch.
A T-handle attaches to one end of the control cable. The other end attaches to the actuation lever.
Location
The waste tank drain ball-valve and control cable are in the bulk cargo compartment on the left side. There is a valve and cable for each waste tank. The valve is under the waste tank and the cable goes between the valve and the waste service panel.
Functional Description
The actuation lever opens and closes the valve. The limit switch stops the operation of the vacuum blower when the valve is not closed. You operate the valve from the service panel. Pull the T handle to open the valve.
Training Information Point
There is a heater blanket around the ball-valve. This prevents any liquid in the valve from freezing.
See the drain and water supply system section for more information on the heater blanket (SECTION 30-71).
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VACUUM WASTE SYSTEM -WASTE TANK DRAIN BALL-VALVE AND CONTROL CABLE
EFFECTIVITY BEJ ALL 38-32-00
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D633W101-BEJ Jan 05/2002
VACUUM WASTE SYSTEM -WASTE DRAIN VALVE ASSEMBLY
Purpose
The waste drain valve assembly gives these features:
*
Double backup seals to prevent leakage from the waste tanks
