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MAINTENANCE MANUAL MODELS 825Y, 825YA, 825, 825D, 825YD & 826YD
6. Relief Valve Reassembly Model 825Y (
3
/
4
–2")
(See Figure No. 11)
a.
Lubricate the seat ring o-ring with FDA approved lubricant
and thread seat ring into the valve body until seated. Do not
over tighten. (Replaceable relief valve seat ring standard on
units manufactured after October of 1988.)
b.
Position the discharge shield over the seat ring diameter
and, taking care not to damage the two flow passages, rein-
stall o-rings and guide bushings.
c.
Carefully place the relief valve body over the bushing and
tighten the two capscrews to retain the relief valve body to
the main valve body. New capscrew sealing washers should
be installed to avoid leakage.
d.
Lubricate the o-rings and main stem using FDA approved
lubricant. Place the main stem and spring into the guide and
replace the flat head screw located at the center button.
e.
Place the disc washer and seat disc in position and retain
with machine screw. Depress the diaphragm button to
ensure it is free moving.
f.
Place the relief valve module into the relief valve body and
mount the diaphragm. Be careful to position the diaphragm
over the port bushing. Replace the relief valve cover and
tighten the capscrews.
g.
After completing reassembly by, slowly open the inlet shut-
off valve. Then bleed air from each chamber and from the
relief valve cover by opening test cocks # 4, # 3, and # 2.
See Figure No. 7 for test cock locations. Slowly open outlet
shut-off valve and return the valve to service.
h.
Test the assembly to ensure it is operating properly.
Service Procedure 825Y and YA (
3
/
4
–2") (Cont.)
