Asco RedHat 8321 Series Installation and operating instructions

Page 1 of 3
50 Hanover Road, Florham Park, New Jersey 07932 www ascovalve com All Rights Reserved
E176965
Installation & Maintenance Instructions SERIES
I&M No.V7538
8321
3-WAY IN ERNAL PILO -OPERA ED SOLENOID VALVES
3/8I AND 1/4I NP
NORMALLY CLOSED AND NORMALLY OPEN OPERA ION
NOTICE: See separate solenoid installation and
maintenance instructions for information on: Wiring,
Solenoid Temperature, Cause of Improper Operation and
Coil Replacement.
DESCRIPTION
Series 8321 valves are 3-way , internal pilot operated, piston type
solenoid valves. Valves may be provided wit a general
purpose/watertig t, open frame, or watertig t/explosionproof
solenoids.
OPER TION
Normally Open:
Solenoid De-energized: Flow is from Pressure P" to Cylinder A",
Ex aust E" connection is closed.
Solenoid Energized: Flow is from Cylinder A" to Ex aust E",
Pressure P" connection is closed.
Normally Closed:
Solenoid De-energized: Flow is from Cylinder A" to Ex aust E",
Pressure P" connection is closed.
Solenoid Energized: Flow is from Pressure P" to Cylinder A",
Ex aust E" connection is closed.
NOTE: To c ange from normally closed operation to normally open
operation, consult ASCO.
(CYL)
A(CYL) A(CYL) A(CYL) A
E
(EXH) E (EXH) E (EXH) E (EXH)
P
(PRESS) P (PRESS) P (PRESS) P (PRESS)
NORMALLY CLOSEDNORMALLY OPEN
FLOW DIAGRAMS
DE-ENERGIZED ENERGIZED DE-ENERGIZED ENERGIZED
IMPORT NT: minimum operating pressure differential of 10 psi
is required.
Manual Operation
Valves wit suffix MO" or MS" after catalog number are provided
wit a manual operator w ic allows manual operation w en desired
or during an interruption of electrical power.
C UTION: For valve to operate electrically, manual
operator stem/lever must be fully rotated counterclockwise.
INST LL TION
C eck nameplate for correct catalog number, pressure, voltage,
frequency, and service. Never apply incompatible fluids or exceed
pressure rating of t e valve. Installation and valve maintenance to be
performed by qualified personnel.
Temperature Limitations
Valves wit design c ange letter K" or P" wit in t e catalog number
(example: 8321K004) ave a maximum fluid temperature of 180F.
Refer to separate solenoid Installation and Maintenance Instructions
for maximum ambient temperature.
Positioning
T is valve is designed to perform properly w en mounted in any
position. However, for optimum life and performance, t e solenoid
s ould be mounted vertically and uprig t to reduce t e possibility of
foreign matter accumulating in t e solenoid base sub-assembly area.
Piping
Connect piping or tubing to valve according to markings on valve
body. Apply pipe compound sparingly to male pipe t reads only. If
applied to valve t reads, t e compound may enter t e valve and cause
operational difficulty. Avoid pipe strain by properly supporting and
aligning piping. W en tig tening t e pipe, do not use valve or
solenoid as a lever. Locate wrenc es applied to valve body or piping
as close as possible to connection point.
IMPORT NT: To protect the solenoid valve, install a
strainer or filter, suitable for the service involved, in the inlet
side as close to the valve as possible. Clean periodically
depending on service conditions. See SCO Series 8600,
8601 and 8602 for strainers.
M INTEN NCE
WARNING: o prevent the possibility of death,
personal injury or property damage, turn off electrical
power, depressurize solenoid valve, and vent fluid to a
safe area before servicing.
NOTE: It is not necessary to remove t e valve from t e pipeline for
repairs.
Cleaning
All solenoid valves s ould be cleaned periodically. T e time between
cleanings will vary depending on t e medium and service conditions. In
general, if t e voltage to t e coil is correct, sluggis valve operation,
excessive noise or leakage will indicate t at cleaning is required. In t e
extreme case, faulty valve operation will occur and t e valve may fail to
open or close. Clean valve strainer or filter w en cleaning t e valve.
Preventive Maintenance
Keep medium flowing t roug t e valve as free from dirt and
foreign material as possible.
Periodic exercise of t e valve s ould be considered if ambient or
fluid conditions are suc t at corrosion, elastomer degradation,
fluid contamination build up, or ot er conditions t at could
impede solenoid valve s ifting are possible. T e actual frequency
of exercise necessary will depend on specific operating conditions.
A successful operating istory is t e best indication of a proper
interval between exercise cycles.
Depending on t e medium and service conditions, periodic
inspection of internal valve parts for damage or excessive wear is
recommended. T oroug ly clean all parts. If parts are worn or
damaged, install a complete rebuild kit.

I&M No V7538
50 Hanover Road, Florham Park, New Jersey 07932 www ascovalve com
Page 2 of 3
Causes Of Improper Operation
Incorrect Pressure: C eck valve pressure. Pressure to valve must
be wit in range specified on nameplate.
Excessive Leakage: Disassemble valve and clean all parts. If parts
are worn or damaged, install a complete ASCO Rebuild Kit.
Valve Disassembly
1. Disassemble valve in an orderly fas ion using exploded views for
identification of parts.
2. Remove solenoid, see separate instructions.
3. If t e valve as a manual operator, refer to section on Manual
Operator Disassembly".
4. Unscrew solenoid base sub-assembly and remove core spring,
core assembly and body gasket.
5. A 4-40 mac ine screw provided in ASCO Rebuild Kit serves
as a self-tapping screw to remove insert from body. Turn screw
a few turns into t roug ole located in flat surface of t e insert.
C UTION: Do not damage center hole (pilot orifice) in raised
surface of insert. Remove insert by using a pair of pliers to grip
t e ead of t e screw.
6. Remove t ree gaskets from insert. Tag eac as t ey are
removed so t at t ey can be reassembled in t e same location.
Middle and lower gaskets ave t e same p ysical dimensions,
owever, t e lower gasket is a softer material. Remove disc
older sub-assembly and disc spring.
7. Remove end cap, end cap gasket and outer piston gasket.
8. Slide out piston assembly and inner piston gasket.
9. All parts are now accessible to clean or replace. Replace worn
or damaged parts wit a complete ASCO Rebuild Kit.
Valve Reassembly
1. Reassemble valve using exploded view for identification and
placement of parts.
2. Lubricate all gaskets wit DOW CORNING 111 Compound
lubricant or an equivalent ig -grade silicone grease.
3. Replace inner piston gasket and slide piston assembly into valve
body.
4. Replace outer piston gasket, end cap gasket and end cap
Torque end cap to 60"10 in-lbs. [6,8"1,1 Nm].
5. Position lower insert gasket and disc older spring
6. Snap upper and m,middle insert gaskets into grooves of insert.
Lower insert gasket fits into t e recess between t e lower
corner of t e insert and t e lower corner of t e body insert
cavity. Middle and lower insert gaskets are t e same size.
However, t e lower gasket is made of a softer material.
7. Place disc older assembly into insert. Install insert (wit gaskets
and disc older assembly) into body cavity, making certain t at t e
disc older spring is centered.
8. If t e valve being rebuilt as a manual operator, refer to section on
Manual Operator Reassembly."
9. Replace t e solenoid base gasket, core assembly wit spring.
10. Replace solenoid base sub-assembly (wit core assembly) into
valve body. Torque solenoid base sub-assembly to 175$25
in-lbs. [19,8$2,8 Nm].
11. Install solenoid, see separate instructions and make electrical
connections.
WARNING: o prevent the possibility of death,
serious injury or property damage, turn off electrical
power, depressurize solenoid operator and/or valve,
and vent fluid to a safe area before servicing.
12. Restore line pressure and electrical power supply to valve.
13. After maintenance is completed, operate t e valve a few times
to be sure of proper operation. A metallic click signifies t e
solenoid is operating.
Manual Operator Disassembly
WARNING: o prevent the possibility of death,
serious injury or property damage, turn off electrical
power, depressurize solenoid operator and/or valve,
and vent fluid to a safe area before servicing.
1. Remove retaining screws (2)
2. Slide out manual operator stem/knob/retainer sub-assembly.
3. Remove stem gasket, guide and guide gasket. Remove spring
(Suffix MS) only.
4. All manual operator parts are now accessible to clean or
replace. Replace worn or damaged parts wit a complete
ASCO Rebuild Kit.
Manual Operator Reassembly
1. Reassemble manual operator using exploded view for
identification and placement of parts.
2. Lubricate all gaskets wit DOW CORNING 111 Compound
lubricant or an equivalent ig -grade silicone grease.
3. Replace guide gasket, guide and stem gasket. Replace spring
(Suffix MS) wit small end on stem first.
4. Screw stem/knob/retainer into valve body using two retaining
screws. Torque retaining screws to 25"5 in-lbs. [2,8"0,6 Nm].
ORDERING INFORM TION
FOR SCO REBUILD KITS
Parts marked wit an asterisk (*) in t e exploded views are supplied
in Rebuild Kits. W en Ordering Rebuild Kits for ASCO valves,
order t e Rebuild Kit number stamped on t e valve nameplate. If t e
number of t e kit is not visible, order by indicating t e number of kits
required, and t e Catalog Number and Serial Number of t e valve(s)
for w ic t ey are intended.

Page 3 of 3
50 Hanover Road, Florham Park, New Jersey 07932 www ascovalve com
I&M No V7538
orque Chart
Part Name orque Value Inch-Pounds orque Value Newton-Meters
solenoid base sub-assembly 175 ± 25 19,8 ± 2,8
end cap 60± 10 6,8± 1,1
retaining screw (manual operator) 25± 5 2,8± 0,6
4-40 machine screw
serves as a self-tapping
screw to remove insert
from body Remove screw
from insert before reassembly
solenoid base
sub-assembly
core spring
core assembly
body gasket
upper insert gasket
insert
middle insert gasket
lower insert gasket
disc holder assembly
disc spring
valve body
end cap
end cap gasket
guide gasket
stem gasket
outer piston gasket
inner piston gasket
piston assembly
MANUAL OPERATOR
Suffix MO"
valve body
guide
retaining screw (2)
stem/knob/retainer
sub-assembly
Figure 1 Series 8321
Indicates Parts Supplied
In ASCO Rebuild Kits
PILO ORIFICE
DO NO DAMAGE
CAU ION
Notes:
1 Middle and lower insert gaskets have the same physical
dimensions However, the lower insert gasket is made of a softer material
2 Upper and middle insert gaskets snap into grooves of insert Lower
insert gasket fits between recess in lower corner of insert and lower
corner of body pilot insert bore
MANUAL OPERATOR
Suffix MS"
retaining screw (2)
stem/knob/retainer
sub-assembly
spring