Cashco 8900 - Manual (Page 4)

4 IOM-8900 Series
3. According to stack orientation of the
diaphragms E.1 previous, lay new diaphragms (2) in
the pallet (3) groove. Align holes in diaphragm (2)
bolt circle over studs (29) in the pressure pallet (3).
4. Position diaphragm retainer ring (4) over
studs (29) resting fl at against the diaphragms (2).
Install 1 lock washer (26) and 1 nut (27) to each stud
(29), tighten to 5 ft. lbs. NOTE: Do not allow studs
(29) to rotate and protrude out the backside of the
pallet (3), end point of studs should be fl ush.
NOTE: For Model 8910 Vents proceed to IV. H.
For Vacuum Pallet:
1. Place threaded end of pallet stem ( 21) in a
soft-jaw vise with pallet (18) face up.
2. Remove the cotter pin (56), nut (24), lock
washer (23), and the fl at washer (22).
3. Remove vacuum pallet (18) and diaphragm
(19). Clean pallet (18), especially the pallet groove
and inspect for nicks or sctatches. NOTE: Vacuum
pressure set point will dictate the quantity and stack
orientation of diaphragms. Record diaphragm’s
stack orientation for re-assembly.
4. Install new diaphragm(s) (19) over short
threaded end of stem (21) onto retainer plate (20).
Apply a light coat of TFE paste on the top surface
of the last diaphragm (19) around the edge of the
center hole.
5. Place vacuum pallet (18) with the machined
groove facing down on the diaphragm (19). Apply a
light coat of TFE paste to short threaded end of stem
(21).
6. Install fl at washer (22), lock washer (23)
and nut (24) onto the protruding threads of the stem
(21). Use a torque wrench to tighten nut to 15 ft-lbs.
7. Insert cotter pin (56) thru small hole in the
stem (21) and wrap prongs around stem.
F. Vacuum Seat Ring Replacement:
- For ERV without Flame Screen:
NOTE: Installation of the pressure pallet diaphragms
should be completed prior to installation of the
vacuum seat ring.
1. Re-Orient the pressure pallet assembly (3)
with vacuum seat ring (8) face down - use 4” x 4”
blocks as support. DO NOT ALLOW DIAPHRAGM
(2) OR RETAINER RING (4) TO REST ON THE
BLOCKS.
C. Removal of Pressure Pallet Assembly:
1. Rotate nut (35) CCW three revolutions
on each adjusting screw (31) to loosen connection
between adjusting screw and pallet guide (30).
Grasp adjusting screws (31) with hand and rotate
each one CCW to remove adjusting screws and
travel stops (37).
2. Remove lower spring buttons (32) (hole w/
large I.D.). NOTE: Not necessary to remove pallet
guides (30) or guide pin (75). (Factory installed with
Loctite - torqued to 15 ft-lbs.)
3. Carefully lift the pallet assembly (3) up off
the fl ange seat (1), so not to damage the seating
surface. Inspect the seat surface for any damage
including but not limited to nicks and corrosion. If
damage is found, the seat should be relapped
or remachined to smooth fi nish. If remachining
is required, contact Cashco/Valve Concepts for
assistance.
D. Inspection of Diaphragms:
1. Position the pressure pallet assembly (3) on
a work bench with the diaphragm (2) side face up.
2. Inspect the diaphragms (2,19) on both
pallet assemblies (if applicable) for any signs of
damage. Damages may include but are not limited
to tears, crinkles/creases, and holes. If it is deemed
that the diaphragm(s) need to be replaced, proceed
with following steps to replace. If they are deemed
to be in good condition, inspect the vacuum seat
ring (8) for similar damages as for the fl ange seat
(1) seating surface. These include but are not
limited to nicks and corrosion. If damage is found,
the seat surface may be relapped. If relapping the
seating surface does not create a suitable seating
surface, a new seat ring is required. Contact your
local representative for assistance. Provide Serial
Number, Product Code & Set Point Pressure(s) to
place an order for parts.
E. Diaphragm Replacment:
For Pressure Pallet:
1. Remove hex nuts (27), lock washers (26),
and diaphragm retainer ring (4) from the pallet.
NOTE: Pressure set point will dictate the quantity
and stack orientation of diaphragms. Record
diaphragm’s stack orientation for re-assembly.
2. Remove diaphragm (2). Clean the pressure
pallet (3), especially the pallet groove, and inspect
for nicks or scratches.