Installation & Operation Manual
Stainless Steel 180° Washfountain
WWF-4203-PSL-FT / WWF-4204-PSL-FT
Willoughby Industries, Inc.
TOLL FREE
(800) 428-4065
● LOCAL
(317) 875-0830
● FAX
(317) 875-0837
Page 15
Rev. 1/2019
www.willoughby-ind.com
Self-closing Pneumatic Valve-
Operation Details
Hand Push Button (released)
Hand Push Button (depressed)
Fixture Backsplash
Fixture Backsplash
VALVE CLOSED
VALVE OPEN
Three Major Components:
(A) Remote push button assembly
(B) Pneumatic servomotor
(C) Servomotor supply valve
Stainless steel separator cup (D)
divides the servomotor & supply valve�
The only interconnection is magnetic force
Valve Closes: releasing the push button relieves pressure
through the hose barb (8) into the chamber above the
actuating diaphragm (2). The lack of air pressure in this
chamber allows the diaphragm (2) and the magnet (3) to
be forced up. The water side actuating disk (4) drops,
covering the pilot orifice (5). Water pressure increases
above the seat diaphragm (6), closing the diaphragm (6)
against the seat (7)�
Valve Opens: Depressing the button (1), forces air through
the chamber above the actuating diaphragm� The air
pressure on top of the actuating diaphragm (2) causes the
diaphragm and magnet (3) to be forced down� The water
side actuating disk (4) is pulled up by magnet (3) opening
the pilot orifice (5), bleeding off line pressure from above
the seat diaphragm (6)� Water pressure then lifts the seat
diaphragm (6) off the seat (7) and opens the valve.
