Electrolux 2.7 Cu. Ft. Tubs, Руководство по обслуживанию

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Water inlet valve
The water valve is mounted to the rear panel under
the main top in the right-hand side.
The water inlet valve is actually two solenoid operating
valves in one body - a hot water valve and a cold water
valve that discharge into a common mixing chamber. The
flow of water out of the chamber is controlled by a molded
in flow washer capable of maintaining a flow rate of 3.0
- 14.6 gallons per minute, with incoming water pressure
of 30 to 120 P.S.I. The inlet valve is controlled by the timer
and water temperature selector switch, individually or
together, to provide hot, cold, or warm water for washing
and cold or warm water for rinsing. The temperature of the
warm mixture will be dependent upon the temperature
and pressure of the hot and cold water supply lines or the
auto temp control.
Valve operation
Both inlet solenoid valves are identical in construction
and operation. The valve body provides an air passage
with a large orifice and seat where the water can be
stopped. The outlet of the valve body empties into the
mixing chamber. A moveable rubber diaphragm
operates against the valve seat to start and stop the
flow of water. The diaphragm is operated by water
pressure. It has a small bleed orifice outside the seat
contact area, and a large main orifice at its center. The
armature of the solenoid serves to open and close the
main orifice. The armature operates within a closed
metal tube (valve guide) which is sealed by the outer
edge of the diaphragm to the valve body. A coil spring
holds the armature down against the diaphragm main
orifice when the solenoid is not energized.
The following line drawings and text explains basic
valve operation.
When the valve is in a closed position, the solenoid is not
energized. Water has bled through the diaphragm bleed
orifice placing incoming line pressure on top of the
diaphragm. The bottom of the diaphragm is essentially at
atmospheric pressure (open to the outlet) and the
pressure differential holds the valve shut.
Water Valve Closed
When the solenoid is energized, the resulting
magnetic field pulls the armature up into the valve guide.
The armature spring is compressed by this action. When
the armature moves up, it allows the water on the top of
the diaphragm to drain through the main orifice.
The diaphragm bleed orifice is much smaller than the
main orifice and will not admit enough water to
maintain pressure on the top side of the diaphragm.
Thus, as the pressure on the top of the diaphragm is
reduced to almost zero, the pressure on the bottom lifts
the diaphragm off the valve seat, allowing a full flow of
water.
Solenoid Activated