MKS HPS 145 Vacuum Sentry Series User manual

Vacuum Sentry
TM
Safety V alve
HPSTM Products Series 145
Vacuum SentryTM
Safety Valve
Operation and Maintenance Manual
651 Lowell Street
Methuen, MA 01844
Main Telephone: [phone] p/n 100010033
www.mksinst.com Rev. A2

Vacuum Sentry
TM
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Part # 145 - _ _ _ _ _ - _ _ _ _ _ _ - _ _
Serial # _ _ _ _ _ _
Please fill these numbers and have
them readily available when calling for
service or additional information.
(The part number can be found on your
packing slip, and both the part number
and serial number are located on the
bottom side of the housing.)
For more information or literature, contact:
MKS Instruments, Inc.
Phone: [phone]
www.mksinst.com
2015 MKS Instruments, Inc., HPSTM Products Inc. All rights reserved
IgniTorr, LoPro, HPSTM and Cv are trademarks and MODUCELL, VACUUM SENTRYTM and AUTO-SOFT are registered
trademarks of HPSTM , a division of MKS Instruments, Inc. SensaVac and Baratron are registered trademarks of MKS
Instruments, Inc. Elgiloy is a registered trademark of Elgiloy Co. OFHCis a registered trademark of Amax, Inc. VCR is a
registered trademark of Cajon Company. Freon, Teflon and Krytox are registered trademarks of E.I. DuPont de nemours & Co.,
Inc. Dust-off is a trademark of Falcon Safety Products, Inc., Mountainside, NJ.

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TM
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Table of contents
Table of contents ....................................................................... 3
Package Contents ..................................................................... 1
Symbols Used in this Manual .................................................... 1
General Description of Vacuum SentryTM ............................................................. 2
Operating PrinciplesVacuum SentryTM................................................................... 3
Vacuum SentryTM Operation Sequence .................................................. 4
Normal Operation - Open position................................................................................ 4
Power Interruption ......................................................................................................... 4
Valve closed - Mechanical pump vented ...................................................................... 5
Power restored .............................................................................................................. 5
Specifications ............................................................................ 6
Installation ................................................................................. 7
Electrical ................................................................................................. 7
Mechanical ............................................................................................. 7
Service ...................................................................................... 8
Disassembly ........................................................................................... 8
Repair of Subassemblies........................................................................ 9
Piston / Diaphragm Subassembly ................................................................................ 9
Nose Piece O-ring Replacement.................................................................................. 9
Bonnet Subassembly .................................................................................................. 10
Reassembly ................................................................................................................ 10
Troubleshooting ....................................................................... 12
Valve Cannot Be Pumped Down to High Vacuum ................................ 12
Valve Leaks in Closed Position............................................................. 13
Valve Closes Too Slowly ....................................................................... 13
Valve Opens Too Slowly or Not Completely ......................................... 13
Valve Fails to Open............................................................................... 13
Closing Causes Large Burst of Air into System ................................... 14
Solenoid Valve is Hot ............................................................................ 14
Factory Repair ...................................................................................... 15
Accessories / Part Replacement ............................................. 16
Product Warranty..................................................................... 17
Notes....................................................................................... 1

Package Contents
Vacuum Sentry
TM
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1
Before unpacking your Series 145 Vacuum SentryTM, check all surfaces of
the packing material for shipping damage.
Please be sure that your Series 145 Vacuum SentryTM package contains
these items:
1 Series 145 Vacuum Sentry
TM
1 Series 145 Vacuum SentryTM Manual
Inspect the Series 145 for visible evidence of damage. If it has been damaged
in shipping, notify the carrier immediately. Keep all shipping materials and
packaging for claim verification. Do not return the product to HPS
TM
Symbols Used in this Manual
The first two symbols below, that may be located on your Series 145
Vacuum SentryTM , identify critical safety concerns. They are used
throughout this manual to further define the safety concerns associated
with the product.
The last two symbols identify other information in this manual that is
essential or useful in achieving optimal performance from the Series 145
Vacuum Sentry
TM
.
CAUTION: Risk of electrical shock.
CAUTION: Refer to manual. Failure to read message could result
in personal injury or serious damage to the equipment or both.
Failure to read message could result in damageto the equipment.
Calls attention to important procedures, practices, or conditions.

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General Description of
Vacuum SentryTM
HPSTM Products Series 145 Vacuum SentryTM is a safety valve, which
protects a vacuum system in the event of power failure by isolating the
vacuum system and venting the mechanical pump. This avoids oil back
up and allows the motor to restart the pump more easily. Vacuum
SentryTM is offered with the ISO-KF flange sizes and solenoid voltages /
frequencies most commonly found on mechanical pumps. Since it
operates with atmospheric pressure and activates upon loss of electrical
power, the novel design requires no external pressurized gas source.
Fast acting Vacuum SentryTM is light weight, constructed of vacuum
compatible materials, and maximizes pumping conductance. Lifetimes in
excess of 100,000 cycles are typical, which translates into years of
trouble free use in suitable environments. The opening burst is less than
the critical backing pressure for turbomolecular and diffusion pumps,
when appropriately sized mechanical pumps are used. The closing burst
minimized by the unique patented buffer volume design. Vacuum
SentryTM consumes little power. Installation is simplified, because the
standard ISO-KF dimensions are used for the NW 40 KF and NW 50 KF
sizes, allowing the valve to replace elbows, Tees, and crosses of the
same size. Even when the mechanical pump is equipped with an integral
anti-suckback valve, Vacuum SentryTM should be used, because the
pump’s integral valve will not vent it and is undependable.

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3
Operating Principles
Vacuum SentryTM
Vacuum SentryTM’s solenoid valve is connected in parallel with the
mechanical pump’s electrical supply either at its source or at the pump’s
switch. See figure 1. When the electrical power is on, the solenoid valve is
closed, allowing the pump to keep Vacuum SentryTM’s body and the vacuum
system evacuated. Interruption of electrical power to the mechanical pump
causes the solenoid valve to open admitting air into Vacuum Sentry
TM
causing it to close very quickly. This isolates the vacuum system from the
mechanical pump, while the pressure deferential between the outside
atmosphere and the vacuum system provides the force to maintain the
valve in its closed position without electrical or pneumatic power. With the
vacuum system isolated, a series of small orifices admits air to the inlet port
of the mechanical pump until it has risen to atmospheric pressure. When
the mechanical pump is restarted, it evacuates the area above the piston
until the pressure is lowered to approximately that of the vacuum system.
Vacuum SentryTM automatically opens again allowing the vacuum system to
be pumped at the full speed of the mechanical pump.

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TM
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Vacuum SentryTM Operation Sequence
The mechanical pump is connected to the port on the right
side and the vacuum system to the bottom port.
Normal Operation - Open position.
Power is on to mechanical pump and Vacuum SentryTM. The
mechanical pump, inlet side of the Vacuum SentryTM, and the
Vacuum SentryTM are all under vacuum at approximately the
same pressure. The spring is holding Vacuum SentryTM open,
and the vacuum system is exposed to the mechanical pump’s
full pumping speed.
Power Interruption
The Vacuum SentryTM solenoid loses its power, since it is
connected in parallel to that of the mechanical pump. The
solenoid opens to the atmosphere. Air enters the Vacuum
SentryTM through the solenoid and creates a higher pressure
above the piston than exists below it. The piston closes
rapidly (30 milliseconds). During this time only the inside of
the piston (buffer volume) is being filled, isolating the vacuum
system from any introduction of air. The figure shows the
piston in transit downward.

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TM
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5
Valve closed - Mechanical pump vented
The piston is fully down and Vacuum SentryTM is fully
closed. The higher pressure above the piston forces it
against the valve seat, where the Viton O-ring makes a
vacuum tight seal. Air from the higher pressure area above
the piston continues through the small orifice in the top of
the piston into the inside of the piston, and through a second
small orifice in its side into the mechanical pump’s inlet port.
This vents the mechanical pump to atmospheric pressure
gradually. When the pump is fully vented, the pressure
above the piston, inside the piston, and in the mechanical
pump are the same (atmospheric). The pressure below the
piston, in the vacuum system, is still lower and the piston
remains down (closed), retaining the vacuum system under
vacuum.
Note that , given enough time, the pressure in the
vacuum system will rise due to outgassing, leaks, etc.,
or venting by the operator, and when the pressure is
high enough, the spring will open the piston and the
vacuum system will be at the same pressure as the
mechanical pump (atmospheric).
Power restored
The solenoid coil is energized causing the solenoid to
close, isolating the inside of Vacuum SentryTM from the
outside atmosphere. The mechanical pump evacuates the
inside of the piston through the small orifice in its side and
the area above the piston through the small orifice in the
top of the piston via the inside of the piston. When the
pressure above the piston is approximately equal to that in
the vacuum system, the spring pushes the piston upward,
fully opening Vacuum SentryTM. The vacuum system is now
back in normal operation and exposed to the full pumping
speed of the mechanical pump.

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Specifications
Nominal body ID 2 inches (50mm)
Leak rate
- body < 1 x 10-9 T-l/s
- seal < 1 x 10-9 T-l/s
Closing time 30 ms
Closing burst 1 x 10-3 T-l
Power 7 Watts @ 115 VAC
Materials
- body & flanges extruded aluminum A1 6061-T6
- piston machined aluminum A1 2024
- seals (O-ring & diaphragm) Viton
- guide pin 304 stainless steel
Temperature range (valve) 0o to 100o C
Temperature range (solenoid) 0o to 50o C
Venting time 10s/lof vented volume(NW 40 & 50)
50 s/l of vented volume (NW 25)

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TM
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7
Installation
Electrical
The solenoid coil leads should be connected in parallels to the rotary vane
pump electrical source, preferably at the pump switch. Be sure that the
solenoid voltage and frequency are compatible with those of the pump
motor. In the case of three phase electrical power, the solenoid may be
connected to one leg and ground.
Ground the solenoid securely using the provided lug before
operation.
Mechanical
Vacuum SentryTM is installed between the mechanical pump and vacuum
chamber or high vacuum pump. Refer to figure 1. Note that the flow arrows
on the unit’s label point from the vacuum system to the mechanical pump.
While it is preferable to mount it directly on the mechanical pump, it may be
located remotely. For best performance, the maximum volume should be on
the vacuum system side, and the minimum volume on the mechanical pump
side, of the Vacuum SentryTM . Operation is position independent and
standard ISI-KF centering ring assemblies and clamps are used to connect
Vacuum SentryTM . The valve body can operate in ambient temperatures up
to 100o C., but the solenoid is limited to about 50o C., because of the heat
generated by the coil. This should be kept in mind when selecting a
mounting location.
The body of the Vacuum SentryTM is very rugged, and it is difficult to deform
it in any normal piping arrangement used in vacuum systems. It is possible
however that tremendous forces could result from thermal expansion, or
from a long run of pipe cantilevered from a fixed valve. Where this
possibility exists, it is necessary to provide stress relief for the valve by
installing a short bellows, and supporting the attached piping other than with
the valve.
Figure 1
Valves are shipped with plastic snap-on covers over the ports, in order to
protect the delicate seal surfaces and to keep the valve clean. These
covers should be left in place until the moment when the valve is to be
installed in the piping. A single fiber or bit of lint on an O-ring seal is
enough to prevent leak tight sealing. The usual cleaning techniques in
vacuum practice should be observed in installing the valve.
When installing the valve, adequate clearance should be allowed between adjacent
components so there is no sliding of seal surfaces against each other. Flanges that
have been assembled for some time may stick together. They should be separated
gently. Do not set the valve down on the seal surfaces unless theyare protected.

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TM
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Service
Vacuum components must be kept free of both particulate contamination
and all foreign materials which have a significant vapor pressure. Before
repairing a vacuum valve, prepare a clean dust-free work are and use
clean, degreased tools devoted to precision assembly.
Periodically, the Vacuum SentryTM should be tested for proper
operation.
Disassembly
These instructions refer to figure 3, Vacuum sentryTM Assembly View:
1. Remove six 10-32 x 7/8 socket head cap screws (9) from
bonnet (10)
2. Remove bonnet (10) with solenoid valve (18) still attached.
3. Remove diaphragm / piston assembly(4, 3, & 11) by gently
prying up the diaphragm at one edge and pulling free of the
body(7) around the full circumference. Inspect the diaphragm for
holes, tears, or accumulatedcontamination. Also inspect the
orifices (19) and (20) for blockage. Finally, inspect the nose piece
O-ring (5)carefully. If it is scratched or if there is imbedded foreign
material, this O-ringmust be replaced.
The bulk of service can be done with disassembly to this point.
If further disassembly is needed, continue with steps 4-7.
4. Remove four 10-32 x 5/8 socket head cap screws (16) from
side port flange (12).
5. Remove side port flange (12) with O-ring (14).
6. Remove six 10-32 x 5/8 socket head cap screws (16) from
bottom port flange (8).
7. Remove bottom port flange (8), O-ring (15) and return
spring (13). Inspect the seat for scratches, other damage or
contamination that could prevent sealing.

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TM
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9
Repair of Subassemblies
Piston / Diaphragm Subassembly
1. Remove diaphragm (11) from piston by unscrewing
sleeve (3) from the piston using a spanner wrench, or
two 1/8” drill bits, in the 1/8 holes provided in the sleeve.
Inspect orifices(19) and (20) and clean if necessary. Be
careful not to enlarge the orifices, because performance
may suffer. Inspect the diaphragm (11) for holes, tears,
or accumulated contamination. Discard if damaged
2. Inspect the dry bushings (2) pressed into sleeve (3). These
bushings are normally good for several hundred thousand
cycles, but they can be replaced when they have worn out.
A worn bushing can be identified by excessive exposure of
the sintered bronze matrix, which is not normally visible. A
modest amount of lead / TEFLONR flakes in and around the
bushing and pin is normal and does not constitute abnormal
wear of the bushing. If there is any doubt about the
condition of the bushings, they should be replaced.
Removal is readily accomplished by inserting a number 10
machine screw and pulling. There are two 1/4 inch long
bushings used in tandem. After removal of the old bushings
inspect the bore in the sleeve (3) for debris and burrs.
Clean as necessary. Press two new bushings into the bore,
one at a time, flush to the top of the sleeve.
3. To reassemble, place diaphragm (11) on the piston with the
inner bead down and the outer bead up. See figure 3. A
small amount of vacuum compatible grease should be
smeared on the sleeve side of the diaphragm / sleeve
contact area to prevent puckering of the diaphragm during
tightening of the sleeve. Also, if the piston and sleeve have
been decreased prior to assembly, then a small amount of
vacuum compatible lubrication should be applied to the
male threads of the sleeve to prevent seizing of the sleeve
to the piston. DuPont KRYTOXR GPL 206 is acceptable.
Tighten the sleeve hand tight. Do not over tighten, this is
not a vacuum grade seal.
Nose Piece O-ring Replacement
1. The nosepiece O-ring (5) should be removed only if a new
replacement is available. To remove the old O-ring, insert a
sharp pointed tool, such as a machinist’s scribe obliquely
into the ring. The sharp point must not pass through the
seal or the surface of the groove will be damaged. Lift the
seal out with the scribe. Use care not to scratch any of the
sealing surfaces.

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2. Prepare the new seal by smearing a verylight but continuous coat
of a vacuum compatible grease on the O-ring. We recommend
DuPont KRYTOXR GPL 206, which is a high qualityfluorinated
grease offering low vapor pressure, excellent temperature stability
and is chemicallyinert.It is important to not skip thisstep. Tests
have indicated that a dryO-ring nose piece O-ring used in a valve
that has been closed formore than two hours issubject to a
breakaway friction exceeding themodest returnspringforce.
Note that the return spring has intentionally been designed to
be soft so as to minimize the opening pressure burst, thereby
necessitating a boundary layer lubrication at the nose piece
O-ring to control the breakaway friction between the valve seat
and the O-ring.
3. To replace the seal, position the piston (4) so that the
groove faces upward. Be sure that the bottom of the groove
and surfaces of the new O-ring are free of scratches. If
necessary, a suitable solvent may be used to clean the
groove. Particulate contamination may be blown off with
DUST-OFFR or dry nitrogen. Place the prepared O-ring
from step #2 above on top of the groove. Place two thumbs
on the o-ring at points 180o apart, and push the o-ring into
the groove. Avoid twisting the O-ring as it is pushed in.
Then push in the opposite intermediate points, and so on,
until the ring is uniformly in place.
Bonnet Subassembly
1. The bonnet subassembly consists of the bonnet (10), guide
pin (1), and a solenoid valve (18) with fittings. The pin is
press fit into the bonnet. The pin is not replaceable,
therefore if the guide pin is bent, heavily scored, or loose
then the bonnet and the pin will need to be replaced as a
unit by a factory replacement part.
2. If necessary, the solenoid valve (18) may be removed by
unscrewing from the bonnet. Inspect the small O-ring and
seal surfaces for damage. Replace if damaged.
Reassembly
1. Slide the piston / diaphragm subassembly on guide pin (1).
With the piston (4) facing up so it does not slide off of the
guide pin, place the body (7) down over the piston, flat
surface to the diaphragm. Now invert the body with the
bonnet held close and align the bolt holes. Insert six
10-32 x 7/8 socket head cap screws (9) and tighten to 27
inch-lb torque.

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TM
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11
2. With the bottom flange as shown in figure 3, slide O-ring
(15) over the boss. Place the return spring (13) inside the
bottom flange, as shown in figure 3. Place the body
subassembly from step 1 above onto the bottom flange.
Align the bolt holes and insert six 10-32 x 5/8 (16) socket
cap screws. Tighten to 27 inch-lb torque.
3. Place the O-ring (14) into the groove on the side of the
body and position the flange (12) on the body. Be sure that
the O-ring and groove are clean. Insert four 10-32 x 5/8
socket cap screws (16) and tighten to 27 inch - lb torque.
4. Before returning the valve to service it should be leak
tested.
Note that power will need to be supplied to the
solenoid in order to check the integrity of the body seals as
well as the solenoid itself.

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TM
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Troubleshooting
This section is a guide for solving problems that may occur with the HPS
TM
Vacuum SentryTM Valve. Listed below are symptoms with possible causes
and suggestions for help.
Valve Cannot Be Pumped Down to High Vacuum
1. Valve leaks from external atmosphere into vacuum system.
First check that the solenoid has proper electrical power
applied to the coil. If the solenoid appears to be functional,
then carefully leak test with a quality leak detector.
With careless leak detection, a leak a large distance away can
be picked up and the leaking component not found. Some
possible sources of leaks are:
a. Non-sealing flanges between valve and system
may be due to damaged flanges, damaged O-ring,
dirt, loose clamps, or incorrect assembly. Locate
the problem and assemble correctly.
b. If a leak signal is obtained at the solenoid / bonnet
connection, disassemble, clean, and reassemble.
c. A leak signal at the solenoid intake indicates a
defective solenoid valve. Disassembly of the
solenoid valve is not recommended. Install a new
solenoid valve.
If the solenoid valve is replaced by a unit not supplied by
HPSTM, it is the responsibility of the user to insure that it is
sufficiently leak tight to meet the specifications.
d. Leaks are found between the body and the bolted
flanges or bonnet. Isolate the offending seal
interface and disassemble. Inspect for damage or
dirt at the seal surfaces. Clean and reassemble as
described above.
2. Valve is dirty and contaminated with a material that is
outgassing or blocking the orifices. Correct by thoroughly
cleaning the valve.

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Valve Leaks in Closed Position
1. Check for proper installation. The valve has been designed
to vent the roughing pump upon closure. If the valve has
inadvertently been installed backwards it would isolate the
pump and vent the system. Reinstall the valve correctly
with the flow arrow on the body label pointing toward the
mechanical vacuum pump.
2. Nosepiece O-ring leaks. Confirm leak using a leak detector.
Replace O-ring as described previously.
3. O-ring (15) leaks. Check for loose screws. Confirm leak
using a leak detector. Replace O-ring as
described previously.
Valve Closes Too Slowly
1. Inlet filter to solenoid valve is clogged. Clean or
replace filter.
2. Solenoid valve is defective. Replace with a new
solenoid valve.
3. There is excess friction between bushing (2) and guide pin
(1). Clean and repair the bushing and guide pin as
described above.
4. The spring is restricted by contamination. Disassemble,
clean, or replace.
Valve Opens Too Slowly or Not Completely
1. The orifices are partially blocked. Clean and reassemble.
2. There is excess friction between bushing (2) and guide pin
(1). Clean and repair the bushing and guide pin as
described above.
3. The diaphragm or spring is contaminated. Disassemble,
clean or replace, and reassemble.
Valve Fails to Open
1. The solenoid valve has a leak or will not close properly
preventing the evacuation of the chamber over the piston
(4). Check to make sure that electrical power has been
restored to the solenoid valve. If the solenoid valve is
energized then leak check to confirm leak and replace
solenoid, if unit is found to be defective.

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2. Foreline between the mechanical pump and Vacuum
SentryTM has a major leak preventing the evacuation of the
chamber over the piston (4). Isolate and correct the leak.
3. Excess friction between bushing (2) and guide pin (1).
Clean and repair bushing as described above.
4. Nosepiece O-ring is stuck to valve seat due to excess heat,
contamination or the improper installation of a dry
(ungreased) O-ring. Follow the directions in section on
nose piece O-ring replacement.
5. The diaphragm or spring is contaminated. Disassemble,
clean or replace, and reassemble.
Closing Causes Large Burst of Air into System
1. Diaphragm is damaged. Replace with a new diaphragm.
2. Diaphragm has become detached from piston (4) and
sleeve (3). Inspect and reassemble as described above.
Solenoid Valve is Hot
1. This is a continuous duty valve equipped with Viton seals
capable of sustained high temperature operation. A 85o C
temperature rise is normal for this valve.
2. Coil and operating voltage / frequency not matched.
Change the solenoid coil to one with a voltage / frequency
compatible with the pump.
3. The ambient temperature is too high. The ambient
temperature near the solenoid is limited to less than 50o C
due to the temperature rise inherent in the solenoid valve.
Higher temperature rated coils are available on a special
request basis if the ambient cannot be controlled to the 50
o
C temperature limit. Replace the solenoid valve with a
new one if the unit is too hot and verify that the ambient air
temperature is within limits. It is permissible to remote the
solenoid valve up to twelve inches away from the Vacuum
SentryTM using standard 1/4 inch tubing, but this could
adversely affect the closing time. An adapter is available
from HPS
TM
.
If the solenoid valve is replaced by a unit not supplied by
HPSTM, it is the responsibility of the user to insure that it is
sufficiently leak tight to meet the specifications. Further, the
operational characteristics of the Vacuum SentryTM may be
significantly degraded.

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Factory Repair
Vacuum SentryTM was designed for user repair, but occasionally it is
necessary to return a valve to the factory. Before shipping, observe the
following steps:
1. Contact MKS and obtain a Returned Material Report
(RMR) number. Use this number on all packing slips,
boxes, and asked to answer these questions:
a. What is the problem?
b. What are the symptoms and how are they
observed?
c. What is the application?
d. Has the valve been used with any dangerous, toxic,
or radioactive substances? See Product Return
Policy below.
e. Is it an emergency repair?
f. Is it a warranty repair? When was the valve
shipped to you?
g. Who in your organization can answer technical
questions about the use of the valve?
2. Prepare the valve for shipment by capping the ports to
prevent entry of foreign material and to protect the seal
surfaces. Place the valve in a sealed plastic bag, and pack
it securely in a sturdy shipping container. Insert a packing
slip of letter referencing the RMR number.
3. If inspection shows the problem to be a warranty matter, the
valve will be repaired and returned free of charge. If it is not
covered by warranty, you will be charged for repairs.

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Accessories / Part Replacement
Item Quantity Description Part Number
1 1
2 2
3 1
4 1
or
5 1
6 .01 oz.
7 1
8 1
or
or
9 6
10 1
11 1
12 1
or
or
13 1
14 1
15 1
16 10
17 2
or
or
18 1
or
or
or
or
or
19 1
20 1
1
Pin
Bearing, .19”ID X .25”L
Sleeve
Piston NW 40 and NW 50
Piston NW 25
O-ring, 2-142, Viton
Grease, vacuum, KRYTOX
TM
Body
Flange, bottom, NW 25
Flange, bottom, NW 40
Flange, bottom, NW 50
Screw, SHCS, 10-32 x .87”L, SST
Bonnet
Diaphragm
Flange, side, NW 25
Flange, side, NW 40
Flange, side, NW 50
Spring
O-ring, 2-137, Viton
O-ring, 2-151, Viton
Screw, SHCS, 10-32 x .62”L, SST
Protector, flange, NW 25
Protector, flange, NW 40
Protector, flange, NW 50
Solenoid valve 120 Volt / 60 Hz
Solenoid valve 100 Volt / 50 Hz
Solenoid valve 220 Volt / 50-60 Hz
Solenoid valve 208 Volt / 60 Hz
Solenoid valve 24 Volt / 50-60 Hz
Solenoid valve 24 Volt dc
Orifice
Orifice
Spanner wrench
100003946
100003897
100003862
100003861
100005110
100003879
100003907
100003868
100003909
100003869
100003911
100003937
100003870
100003864
100003908
100003866
100003910
100003867
100003878
100003880
100001554
100003046
100003047
100001737
100003865
100003898
100003899
100003900
100003901
100003903
100001695
Item numbers refer to figure 3.
Be sure to have on hand the serial number and flange type when ordering
replacement parts.