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ADAPTOMODE WELD-END
PRESSURE REGULATORS
Types: A4W, A4WE, A4WS, A4WB,
A4WD, A4WP, A4WOE, A4WR
Port Size 125-200mm (5”-8”)
FOR AMMONIA, R12, R22, R502
AND OTHER COMMON REFRIGERANTS
FEATURES
• Cast Steel Body – Strong, Lightweight.
• Welds Directly in the Line – No Flanges.
• Removable Seat – Serviceable from Top Side.
• Streamlined Fluid Flow Pattern.
• Unique Modular Construction – Same Modules
as A4A Series.
• Interchangeable Parts.
• Easy to Service.
• Pilot Operated Characterized Modulating Plug for
Precise Control.
• Suitable for All Common Refrigerants and Oil.
• 27.6 bar (400 psig) Maximum Rated Pressure (MRP).
• Many Control Variations are Possible with the Use
of a Few Modules and Kits.
• Stainless Steel Diaphragm.
• Chrome Plated Pilot Seat.
• Manual Opening Stem.
Seal Cap
Seal Cap
Manual
Opening
Stem
Power
Piston
Removable Seat
Fig. 1 - A4W, A4WE
Adjusting Stem
Range Spring
Diaphragm
Gauge Port
Pilot Seat
Modulating
Plug
Closing
Spring
BULLETIN 23-20D
A4W Series
August 2007
Installation, Service and Parts Information
Index
Item ...................................................................................... Page
A4W .............................................................................................1
A4WB ...........................................................................................3
A4WD ............................................................................................4
A4WE ........................................................................................... 2
A4WOE ......................................................................................2, 4
A4WP ............................................................................................4
A4WR ............................................................................................5
A4WS ............................................................................................3
Adjustment, Range ......................................................................2
Assembly ......................................................................................6
Dimension Drawings ............................................................ 12, 13
Disassembly ................................................................................. 6
Electrical ......................................................................................5
Installation ...................................................................................5
Mintenance and Service ...............................................................8
Manual Opening Stem ............................................................ 8, 9
Pressure Setting Ranges .............................................................2
Safe Operation .......................................................................... 14
Torques, Fastener and Seat ........................................................7
Trouble Shooting ........................................................................ 9
Warning .....................................................................................14
Warranty .....................................................................................14
Description
These heavy duty, cast steel bodied (ASTIM No. A352 Grade
LCB), pressure regulators weld directly in the line and do not
require fl anges.
They are used for control of Ammonia, R-12, R-22 and R-502,
and other common refrigerants, certain oils and other fl uids
approved for use in refrigeration systems.
The A4W Series Regulators are pilot operated, using upstream
pressure for the moving force, and require a minimum 0.14 bar
(2 psi) pressure drop to fully open. The basic Type A4W is an Inlet
Pressure Regulator which tends to open on a rise in upstream
pressure above set-point and to close on a drop in pressure
below set-point.
These valves can be ordered with the Type RSW Strainer to be
welded directly to the inlet of any of the Type A4W Regulators
or use a 13mm (1/2”) Type RSF Strainer in only the pilot circuit
of a Type A4WE or A4WR version of the regulator.
The A4W Series of regulators uses the same Modules as does
the A4A Series to confi gure many possible variations.
Refrigerating Specialties Division
050405
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ISO 9001:2000 CERTIFIED
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Purpose
The purpose of the Type A4W Series of Pressure Regulators is to
modulate the fl ow of refrigerant gas and/or liquid so as to maintain
a constant set for pressure, regardless of load fl uctuations. The
regulators described in this bulletin control upstream (inlet)
pressure except for the Type A4WOE, which controls downstream
(outlet) pressure.
The fl uid temperature range for the A4W Family of Regulators is
-45° to 105°C (-50° to 220°F).
Principles of Operation (See Fig. 1)
The inlet pressure enters the space under the Diaphragm through
passage N. When the force created by the pressure exceeds the
force of the Range Spring, the Diaphragm is lifted off of the Pilot
Seat, allowing pressure to enter on top of the Power Piston.
This causes the Power Piston to move downward, forcing the
Modulating Plug to open and modulate to maintain constant inlet
pressure. (See pages 3 - 5 for principles of operation of other
A4W Variations.) An increase in inlet pressure lifts the Diaphragm
further, allowing more pressure on top of the Power Piston and
opening the valve wider. A decrease in inlet pressure causes the
Diaphragm to move closer to the Pilot Seat reducing the pressure
on the top of the Power Piston and allowing the Closing Spring to
reduce the valve opening.
The degree of valve opening is controlled by the amount of
pressure on top of the Power Piston, which in turn is controlled by
the fl ow through the Pilot Seat and the bleed off through the bleed
hole in the Power Piston to the outlet of the valve. The volume of
bleed fl ow from the top of the Piston to the valve outlet through
the clearance between the Power Piston and the piston bore is
very small because the Power Piston is fi tted with a Seal Ring.
Manual Opening Stem
All Type A4W Regulators are provided with a Manual Opening
Stem located at the top of the valve (refer to Fig. 1 for the location
of the stem and other related parts). For access to the stem
the Seal Cap on top of the regulator must be removed. Manual
opening is accomplished by turning the stem clockwise until only
the fl ats on the end of the stem protrude from the Packing Nut. To
reset for automatic operation, turn the stem counter-clockwise
as far as it goes.
CAUTIONS: 1.) The Seal Cap must be removed with care, as
refrigerant may have been trapped inside the cap. 2.) BEFORE
turning the stem, the Packing Nut should be loosened slightly,
and 3.) AFTER turning the stem, the Packing Nut should be
retightened. 4.) Always replace the Seal Cap when work with the
regulator is completed.
Adjustment
INLET PRESSURE REGULATORS - A4W - (See Fig. 1) Install an
accurate pressure gauge in the gauge port. Back the Adjusting
Stem all of the way out to stop (counterclockwise). This will
reduce the set-point to its lowest level and will cause the valve to
OPEN wide. Start the system, and when the valve outlet pressure
is approaching the desired inlet pressure, turn the Adjusting
Stem in (clockwise) until the pressure gauge shows a slight
rise in inlet pressure. At this point the Adjusting Stem may be
turned in (clockwise) to raise the pressure further, or backed out
(counterclockwise) to lower it, but the fi nal adjustment should be
made after the system has been operating for a period of time and
has stabilized.
OUTLET PRESSURE REGULATORS - A4WOE - (See Figs. 2,
2A) Install an accurate pressure gauge at the gauge port in the
A4WOE Adapter which is located next to the sensing tube that is
connected to the valve outlet line. Back the Adjusting Stem all of
the way out to stop (counterclockwise). This will reduce the setpoint to its lowest level and cause the valve to CLOSE. Operate the
system until the outlet pressure is lower than desired. Slowly turn
the adjusting stem in (clockwise) until the desired outlet pressure
is reached with the system stabilized.
PRESSURE SETTING RANGES
Inlet ranges available are A, V, and D
*Outlet pressure ranges available are V and D
Set-Point Ranges per Turn of (unless otherwise
Adjusting Screw specifi ed)
A: 0 to 10.3 bar 1.7 bar (25 psi) 2.8 bar (40 psig)
(0 to 150 psig)
*V: 500mm hg to 8.3 bar 1.7 bar (25 psi) 1.0 bar (15 psig)
(20 in hg to 120 psig)
*D: 5.2 to 19.3 bar 3.7 bar (53 psi) 9.7 bar (140 psig)
(75 to 280 psig)
A Vacuum Range Regulator uses a Vacuum Cartridge instead of
the standard Pilot Seat 44. Except for this one difference, a “V”
Range Regulator is the same as an “A” Range Regulator as far
as the Range Spring 49 and Diaphragm Kits are concerned. (See
Figs. 7 and 8)
Approx. Pressure Changes Factory Set Point
Fig. 2
Refrigerating Specialties Division
Fig. 2A - Outlet Pilot
Type A4WE (See Fig. 1)
Description
The Type A4WE is the same as a Type A4W except that the upstream
or remote pressure must be fi eld connected to the valve at the
gauge connection through an external line. (The external line is
not furnished with the regulator.) A Type A4W can be converted
to an A4WE by removing the adaptor from the body; remove the
alignment pin from passage ‘N’; and rotate the Gasket 5 to block
off the internal feed of upstream pressure. Re-assemble. (See
)
Fig. 7
Purpose
The Type A4WE is used when it is advantageous to use an external
source of upstream pressure to the regulator. Whatever the
source of pressure may be, it will be that pressure, as it exists
when it reaches the regulator, that will be controlled. There is a
small fl ow rate of fl uid through the external line and care must be
used to avoid a pressure drop by not under sizing the pipe or using
too long a length. Normally a US 3/8” pipe size not exceeding 6m
(20 ft.) in length will be adequate.
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The pressure as measured at the connection to the valve must be
no less than the pressure at the valve inlet.
A 13mm (1/2”) Type RSF strainer can be installed in the above line
to protect the critical pilot circuit of the main valve and eliminate
the space required for and the cost of a full line-size strainer.
If this is done, it should be remembered that any pressure drop
in this line caused by an overloaded strainer basket will affect
the actual pressure at which the regulator will control. If this is
the case, then the actual pressure at the main valve inlet will be
higher than it should be by an amount equal to the pressure drop
through the pilot circuit strainer.
Principles of Operation
The operation of the Type A4WE is the same as that described
above for the A4W except that the upstream pressure being
controlled is fed to the valve externally.
Adjustment
Follow the instructions above for the Type A4W Regulator.
Type A4WS (See Fig. 3)
Description
The Type A4WS is an inlet pressure regulator with a pilot electric
shut off. The integrally mounted solenoid must be energized
for the valve to function as a regulator. When de-energized the
regulator is closed regardless of inlet pressure.
Purpose
The Type A4WS should be used where it is required at particular
times to stop all fl ow through the regulator. The valve, however, is
NOT a check valve and cannot prevent reverse fl ow of fl uid if the
outlet pressure exceeds the inlet pressure by more than 0.14 bar
(2.0 psi). Typical uses include defrost applications as well as part
of a temperature control system.
Principles of Operation
The operation of the A4WS is the same as that described for the
A4W on page 2, except the inlet pressure from passage N must
pass through the S6A Pilot Solenoid Valve before it can reach the
diaphragm. Thus, the S6A Pilot Solenoid must be energized before
the A4WS can begin to regulate, regardless of inlet pressure.
Adjustment
With the solenoid pilot electrically energized, proceed as
described above for Inlet Pressure Regulators.
Fig. 3 - A4WS
Type A4WB (See Fig. 4)
Description
The Type A4WB is an Inlet Pressure Regulator with a Pilot Electric
Wide-opening, or Bypass, variation. When the integrally mounted
solenoid is energized the main valve is wide open thereby
bypassing the regulator function, that is, not regulating. However,
in the wide open mode the regulator will still require the 0.14 bar
(2 psi) minimum pressure difference to be fully open. When the
solenoid is de-energized the valve functions as an inlet pressure
regulator.
Purpose
The Type A4WB frequently is used in the wide-open mode when
maximum refrigeration capacity from an evaporator is required.
During the defrost of the evaporator, the regulator pilot solenoid
is de-energized, thus functioning as a defrost relief regulator or
for high pressure limit protection. Also, this regulator can be used
in the wide open mode for evaporator pump out prior to defrost.
When used in a discharge pressure line, it can, when de-energized,
hold back enough pressure for some heat reclaim or defrosting
function and then, when energized, allow the discharge pressure
to decrease to a lower level.
Principles of Operation
The operation of the A4WB is the same as that described for the
A4W on page 2, when operating as a regulator (Pilot Solenoid Deenergized). When the solenoid is energized the upstream pressure
from passage N bypasses the underside of the diaphragm and
is fed directly to the top of the piston, whereby, provided a 0.14
bar (2 psi) pressure difference exists across the main valve, the
Modulating Plug will be held wide open.
Adjustment
With the solenoid pilot electrically de-energized, proceed as
described above for Inlet Pressure Regulators.
Fig. 4 - A4WB
Type A4WD (See Fig. 5)
Description
The Type A4WD is a Dual Inlet Pressure Regulator capable
of regulating two different pressure set-points. When the
integrally mounted S6A Pilot Solenoid is energized, the regulator
is controlling the lower of the two set-points, which must be
adjusted on the pressure pilot over the center of the main valve.
When the solenoid is de-energized, the regulator is controlling
the higher of the two set-points, which must be adjusted on the
bolt-on (outboard) pressure pilot.
Purpose
The Type A4WD uses are similar to those for the A4WB except
that, instead of operating in a wide-open position when the pilot
solenoid is energized, the regulator is controlling at some preset
level.
Typical uses include capacity control of an evaporator at two
different pressure levels to regulate temperature, or evaporator
pressure control combined with defrost or wash down pressure
relief.
Principles of Operation
The operation of the A4WD is similar to that described for the
A4W on page 2. When the Pilot Solenoid is energized, upstream
pressure from passage N is made available to both diaphragms.
Since the path of least resistance will be through the pilot having
the lower set-point (lower range spring force), that pilot will
control.
When the Pilot Solenoid is de-energized, the upstream pressure
from passage N can fl ow only to the high pressure pilot, which will
then control the regulator.
Adjustment
Electrically de-energize the solenoid pilot and adjust the modular
(bolt-on) pressure pilot for the desired high pressure setting
following the adjusting procedure as described above.
Refrigerating Specialties Division
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Energize the solenoid pilot and adjust the integral pressure pilot
for the desired low pressure setting following the same procedure.
The modular (bolt-on) pilot MUST be adjusted for a set-point
HIGHER than the integral pilot or the regulator will always be
controlling at the lower set-point whether the pilot solenoid is
energized or de-energized.
Fig. 5 - A4WD
Type A4WP
Description
The Type A4WP is an Inlet Pressure Regulator whose setpoint
can be compensated by a remote pressure. Typically the remote
pressure would be a pneumatic signal from a thermostat or
controller, but it can also be a refrigerant pressure. The remote
pressure is fed into the bonnet of the regulator where it is capable
of changing the set-point on a 1:1 basis. That is, a 0.07 bar (1.0
psi) change in the remote pressure will create a 0.07 bar (1.0 psi)
change in the set-point of the regulator.
Although not specifi cally described in this bulletin, the A4WP
is also available with any of the “S”, “B”, “D” and “OE” features
mentioned elsewhere
Purpose
The Type A4WP can be used to vary an evaporator or condenser
pressure to match a changing load condition. A pneumatic
thermostat-controller modulates the air pressure applied to
the top of the diaphragm as the temperature at the thermostat
changes. Whether used as part of a cooling system to control
evaporator pressure, or as part of a Heat Reclaim system to control
condensing pressure, a rise in temperature at the thermostat
must cause a decrease in controlled air pressure. (Normally
this is known as a “Reverse Acting” thermostat-controller.) The
decrease in air pressure will lower the regulator set-point and
produce a lower inlet pressure and lower evaporator or condenser
temperature. Conversely, a drop in temperature at the thermostat
must cause an increase in air pressure, with a resultant increase
in evaporator or condenser temperature. Usually, the controller
modulates the air pressure from 0.21 to 1.0 bar (3 to 15 psig)
throughout its control range.
The A4WP can be used as a Differential Pressure Regulator if the
regulator outlet pressure is connected to the bonnet.
Principles of Operation
The Type A4WP operation is the same as the A4W described above
except that the set-point is changed (compensated) on a 1:1 basis
by the pressure that is fed into the bonnet.
If the A4WP is part of a pneumatically operated control system,
the air must be clean, dry and oil free. To avoid the possibility of
moisture from compressed air freezing in the bonnet or in other
parts of the control system, a dehydrated air system must be used
whenever it may come in contact with sub-freezing temperatures.
This is particularly true if the regulator is controlling suction gas
fl ow at temperatures below freezing.
Adjustment
If the A4WP is part of a pneumatically operated control system.
the controller must be adjusted according to the manufacturers
instructions to obtain the optimum system performance. To
adjust the pressure regulator. disconnect the air line and follow
the instructions, above listed for the Type A4W. This setting
represents the lowest inlet pressure the regulator will allow,
.
thus providing a low limit feature to the regulator. Next, connect
the air line. From this point the regulator’s set-point will be
increased on a 1:1 ratio with the air pressure increase.
If the A4WP is compensated by a remote refrigerant pressure, the
setpoint of the regulator (the inlet pressure it will be controlling)
will be equal to the sum of the remote pressure and the pressure
equivalent to that made by the range spring adjustment. If the
remote pressure is the regulator outlet pressure, then the valve
will control an inlet pressure equal to the outlet pressure plus the
Range Spring setting. Or, said another way, the Regulator will be
a Differential Pressure Regulator because the set-point will be
the difference in pressure across the regulator.
Type A4WOE (See Fig. 2-2,2A)
Description
The Type A4WOE is an Outlet Pressure Regulator with an external,
fi eld installed connection to the downstream (outlet) pipe of the
regulator. This connection is not furnished with the regulator. The
regulator will tend to open on a drop in outlet pressure below
set-point and will tend to close on a rise in outlet pressure above
set-point.
Although not described in this bulletin, the A4WOE is also available
in combination with the “S”, “B”, “D” and “P” features described
elsewhere.
Purpose
The Type A4WOE will modulate fl ow of refrigerant fl uid to
maintain a constant downstream pressure as set-for, despite
fl uctuations in load. However, once closed, the regulator can do
nothing further to reduce downstream pressure. This reduction
must come from system capacity. The regulator cannot maintain
set-for pressure if uncontrolled blanch lines feed into the main
pipeline downstream of the A4WOE Regulator.
Typical applications are as a hold back or crankcase pressure
regulator to prevent pressure rise in a suction main, or to prevent
too low a plant suction pressure by putting an artifi cial load on the
main from a higher pressure source.
Principles of Operation
The outlet pressure is sensed under the Diaphragm through the
external tube which has been installed in the fi eld to the outlet
pipe downstream of the main valve. When the force created by the
outlet pressure acting under the Diaphragm is less than the force
of the Range Spring, the pilot is open, allowing upstream pressure
from passage N to fl ow to the top of the Piston. This causes the
Piston to force the Modulating Plug to open to maintain a constant
outlet pressure. A decrease in the outlet pressure allows the
Range Spring to open the pilot further, allowing more pressure
on top of the piston and opening the Modulating Plug further.
An increase in outlet pressure will lift the Diaphragm against
the force of the Range Spring, allowing the Pilot Plug to start
to close. The pressure on top of the Piston is decreased
and the Closing Spring acts to reduce the opening of the
Modulating Plug and the fl ow of fl uid through the regulator.
Fig. 2-2 - A4WOE
Refrigerating Specialties Division
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The pressure on top of the Piston is controlled by the fl ow through
the Pilot Plug and the bleed through the bleed hole in the Piston.
Due to the Seal Ring fi tted to the Piston, the amount of bleed to
the outlet of the valve, as a result of blow-by of the Piston, is very
small. A minimum pressure drop of 0.14 bar (2 psi) across the valve
is required to open it fully.
The Type A4WOE Outlet Pressure Regulator opens on a drop
in outlet pressure below set-point and closes on a rise in outlet
pressure above its set-point. The outlet pressure set-point is not
appreciably affected by variations in the inlet pressure.
Adjustment
See Outlet Pressure Regulator Adjustment on page 2.
Type A4WR (See Fig. 6)
Description
The Type A4WR is a main valve only intended for pilot operation by
one or more remote piloting devices, such as Type S6N Solenoid
Valve, Type A2B (inlet) or Type A2BO4E (outlet) Pilot Regulators.
The valve is complete with a Manual Opening Stem but has no
integrally mounted pilot devices to provide any type of control
function. A plain Cover with a 3/8” FPT connection is in the position
otherwise occupied by the pilot devices. The
Type A4WR uses upstream pressure which is externally fed to
the A4WR through pipes (not included with valve) fi eld installed to
provide the moving force for the valve operation. A minimum 0.14
bar (2 psi) pressure drop is required to fully open the valve. The
upstream pressure must be fed from a connection fi eld installed in
the main valve inlet pipe. There is no connection on the valve body
for this purpose.
A small fl ow of refrigerant passes through the line connected to
the upstream side of the valve so care must be used not to create a
pressure drop by under sizing the pipe or using too great a length.
Normally standard 3/8” US pipe size no longer than 6m (20 ft.) will
be adequate. Consult the factory if a greater length is required.
Purpose
The Type A4WR should be used where there is an advantage to install
all of the control modules at some remote location. Frequently this
is done to make adjustment and servicing easier, or to fi t a large
valve in a space that would be too small for a complete valve.
Principles of Operation
Since the Type A4WR is a main valve only and may be used with an
assortment of remote devices: the reader is referred to the most
recent editions of the bulletins describing each of those devices.
The most common of these are: Type S6N Solenoid Valve - Bulletin
30-90; Type A2B and Type A2BO4E Regulators - Bulletin 21-02.
Adjustment
See the appropriate bulletin as listed above under “Principles of
Operation”.
Installation
It is necessary that all installation personnel read and become
familiar with the Refrigerating Specialties Division’s Refrigeration
Safety Bulletin (RSB) before installing any valves.
All valves are packed for the maximum protection during storage
and shipment Read the literature packed with the valve and save it
for reference after installation.
Do not remove the protective covers from the inlet and outlet of the
valve until ready to install, as they protect the interior from dirt and
other foreign matter.
Select a location for installation where the valve will be easily
accessible for adjustment and maintenance and where a pressure
gauge installed on the regulator can be seen. Avoid locations where
the valve may be damaged by personnel, traffi c, material handling or
other equipment.
Before installing the valve, check to see that all chips, scale,
dirt, moisture and other foreign material are removed from the
connecting pipes. Be sure the arrow on the A4W valve body is
pointing in the direction of fl uid fl ow for the regulator to function
properly. Backward fl ow through the regulator is uncontrolled and
will vary with the reverse pressure drop encountered. The regulator
is NOT a check valve. Remove the protective covers from the valve. It
is not necessary to disassemble or to manually open the valve before
welding in place.
The A4W family of regulators will give optimum performance if
mounted in a horizontal line in a vertical position with the Manual
Opening Stem on the top. This is particularly true for regulators with
an electrical feature, such as the “B”, “S” or “D” variations. Where
other positions are desired, the factory should be consulted; please
give valve type, application and piping details.
After installation, check the valve and the welded joints for external
leaks with refrigerant or other appropriate gas before putting the
system into operation
If pilot solenoid valves are a part of the regulator, connect the
solenoid lead wires to an electrical supply source the same as
indicated on the valve coil. The power source must be capable of
supplying full, constant voltage. The wires to which the solenoid
leads are connected must be of the proper gauge.
When it is necessary to insulate the regulator (and companion
strainer), the insulation should be installed to allow access to the
regulator (and companion strainer) for adjustment and maintenance.
Do not insulate a solenoid coil and coil housing. Proper indicating
gauges should be installed to be easily visible to the operating
engineer for system checking and adjusting purposes.
Electrical (For A4WS, A4WB and A4WD)
The Refrigerating Specialties Division molded, water resistant Class
“B” solenoid coil is designed for long life and powerful opening force.
The standard coil housing meets NEMA 3R and 4 requirements. This
sealed construction can withstand direct contact with moisture and
ice. The coil housing far exceeds the requirements of NEMA Standard
ICS, 1-110.57 salt spray test for rust resistance.
By defi nition, Class “B” coil construction will permit coil internal
temperatures, as measured by the resistance method, as high as 130
deg. C (266 deg. F). Final coil temperatures are a function of both fl uid
and ambient temperatures. The higher fl uid temperatures require
lower ambient temperatures so the maximum coil temperature is
not exceeded. Conversely, low fl uid temperatures permit higher
ambient temperatures.
The molded Class “B” coil is available, from Refrigerating Specialties
Div. stock, with most standard voltages. However, coils are available
for other voltages and frequencies, as well as for direct current.
Coils are also available as transformer type with a 6 volt secondary
winding for use with the Refrigerating Specialties Division Pilot Light
Assembly. (See current copy of Bulletin 60-10, “Pilot Light Assembly
and Solenoid Transformer Coil”.)
Fig. 6 - A4WR
Refrigerating Specialties Division
The solenoid coil must be connected to electrical lines with volts
and Hertz the same as stamped on the coil. The supply circuits must
be properly sized to give adequate voltage at the coil leads even
when other electrical
equipment is operating. The coil is designed to
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operate with line voltage from 85% to 110% of rated coil voltage.
Operating with a line voltage above or below these limits may
result in coil burn-out. Also, operating with line voltages below
the limit will defi nitely result in lowering the valve’s maximum
opening pressure differential. Power consumption during normal
operation will be 33 watts or less. Note that no coil should ever be
energized when it is not securely mounted on the solenoid tube.
Inrush and running current is listed below:
Inrush Running Fuse
Standard Coil Current Current Size
Volts/Hertz (Amps) (Amps) (Amps)
120/60 (Blue leads) 1.18 0.46 1
208/60 (Blue & Red leads 063 0.26 1
240/60 (Red leads) 0.60 0.23 1
440/60 (Yellow & Red leads) 0.39 0.13 1
115/50 (Yellow & Blue leads) 1.22 0.21 1
230/50 (Yellow leads) 0.65 0.26 1
Other (Contact Factory)
(On transformer coil, the 6 volt leads are always black.)
Disassembly and Assembly
General Procedure (See Figs. 7, 8, 9, and 10)
Before disassembling any A4W type regulator, read the
information in this bulletin and Bulletin RSB (Safety Procedures
for Refrigerating Specialties Division Refrigeration Control
Valves).
Before a regulator is disassembled in the line, make sure that
all refrigerant has been removed from the regulator, including
the Bonnet (where applicable), the close coupled Strainer (if
used) and the adjacent pipes at the inlet and outlet of the valve.
The regulator must be isolated from the rest of the system in a
safe manner. When pumping down to remove the refrigerant, the
Manual Opening Stem 11 must be turned in (clockwise) to make
sure that the valve is open.
All service or disassembly work is done from only the top side of all
A4W Regulators. The construction of the regulator and the method
of disassembly are relatively simple, but some procedures must
be followedto avoid damage or injury. The following describes the
procedure for the basic A4W: special instructions for other types
are included in the appropriate sections.
See Fig. 9 for S6A Pilot Solenoid Valve and Fig. 10 for A2D Pilot
Regulator Valve. See also Bulletin 23-06 for additional information
about the S6A Pilot Solenoid and the A2D Pilot Regulator Valves
.
Disassembly (See Figs. 7, 8 , 9 and 10)
Take care when removing Seal Caps 15 and 57 in case some
refrigerant may be trapped inside. Back the Adjusting Stem 52 all
of the way out (counterclockwise) to remove any pressure from
the Range Spring 49, otherwise damage to diaphragm 45 or Pilot
Seat 44 may occur. Remove Bonnet 51 by carefully removing Cap
Screws 58. Take care not to damage Diaphragm Follower 47.
Turn the Manual Opening Stem 11 all the way out (counterclockwise)
to stop. If for a 125 or 150mm (5” or 6”) Regulator, remove the
Adapter Cover 22 by carefully removing Bolts 17 and Nuts 18. If
for a 200mm (8”) Regulator, remove the Adapter Cover by carefully
removing Bolts 17. (Note: The Studs 19 found on the two smaller
sizes are not used on the 200mm (8”) size.) Carefully lift the
Adapter Cover away from the Body 1 by fi rst breaking the gasket
seal by inserting a fl at tipped screw driver between the two parts
and prying them apart, then lift the Adapter Cover off of the Body
1. On the 125 and 150mm (5” and 6”) valves, the two Studs 19 will
be retained in the Adapter Cover.
The Manual Opening Stem 11 can be removed from the Adapter
Cover 22 as follows: Remove Packing Nut 12 by turning it out
(counterclockwise) from the Adapter Cover. Slide the Packing Nut
over the Manual Opening Stem and then turn the Manual Opening
Stem in (clockwise) until the threads on the stem disengage from
the Adapter Cover. Remove the Manual Opening Stem from the
bottom side of the casting.
Push the Power Piston 9 down against the Closing Spring 8 force.
The Piston should move freely down and be returned by the
spring force. If the Piston is jammed or sticky, insert a US 1/4”20 machine screw into the tapped hole in the center-top of the
Piston and use this screw as a means of lifting the Piston from
place. (It may be helpful to know that the coil housing screw on a
standard Refrigerating Specialties solenoid valve is a 1/4-20 screw
that can be used for this purpose.)
If the Piston 9 cannot be removed as suggested above then use
the following procedure: Obtain a fl at steel bar approximately
10mm x 50mm (3/8” x 2”) x 50 (2”) longer than the diameter of the
piston bore. Drill a hole in the center of the fl at face that will clear
the 1/4”-20 screw. Obtain a 1/4-20 machine screw with a thread
the full length of the bolt that is at least 100mm (4”) long and a
1/4” hex nut. Place the bar across the top of the body bore, thread
the nut on to the machine screw and put the screw through the
clearance hole in the bar and thread it into the hole in the top of
the Piston. Snug the nut down against the bar and then, by further
tightening of the nut, pull the piston out of the body.
Examine the Seal Ring 10 for unusual wear and or tears. The
Seal Ring should appear as is illustrated in Fig. 11 which shows a
cross-section of the edge of the Piston 9 and the manner in which
the Seal Ring fi ts in the piston groove. Look at the bottom end
of the piston stem for signs of hammering or peening that could
be caused by an oversized regulator chattering as it attempts to
control a load far less than its capacity. If either the Seal Ring or
the Piston is damaged, they should be replaced and the cause of
the damage determined and eliminated.
The Valve Seat 2 on all A4W Regulators is removable. A US 3/8”-16
hex head Locking Screw 4 is used to hold the seat in position and
this must be removed using a 9/16 socket wrench. A Seat Wrench
6 is used to remove the Valve Seat. (Each valve size has its own
size Seat Wrench.) Position the prongs of the Modulating Plug so
that it is possible to place the wrench over opposite projections
on the top of the seat. Then, using a standard US 1/2” drive bar,
turn the seat counterclockwise until it comes free. The main valve
Modulating Plug 7 and the Closing Spring 8 can now be removed.
Examine the seating faces of the Valve Seat and the Modulating
Plug for uneven wear, nicks or non-uniform surfaces to determine
if either or both should be replaced. If it is necessary to replace
either part, determine and eliminate the cause of the wear that
necessitated the replacement.
Assembly (See Figs. 7, 8, 9 and 10) To assemble the
Modulating Plug 7 and the Valve Seat 2 it is necessary to have the
appropriate size Seat Wrench 6 (each valve size has its own Seat
Wrench) and a new Seat O-Ring 3. Insert the Closing Compression
Spring 8 into the matching recess in the bottom of the Valve Body
1 so that it is in position to receive the bottom extension of the
Modulating Plug. Next insert the O-ring into position on the Valve
Seat and lightly lubricate with silicone grease. Put the Modulating
Plug through the Valve Seat and by grasping the prongs of the
Modulating Plug place both into the Valve Body so that the
Modulating Plug engages the Closing Spring and the Valve Seat
threads line up with the matching threads in the Body. Using the
Seat Wrench tighten the seat in place to the torque listed in the
table below. Finally, replace the Retaining Screw 4 and tighten with
a 9/16” socket wrench to the torque listed in the table below.
To replace the Seal Ring 10 on the Power Piston 9 install in place
by starting the new ring over the top of the Piston. Gradually
engage the ring into the slot, rotating the force on the ring as it is
pushed into place. The Seal Ring must be installed as shown in
Fig. 11 with the open edge of the ring pointing up.
Before installing the Power Piston 9 in the body bore be sure that
the bleed hole in the top of the piston is clear. Insert the Piston
into the Body 1 so that the top of the Piston is parallel with the
top of the Valve Body and, with an even force, push the Piston
into the Body. There is no fasteningbetween the Piston and the
Modulating Plug 7; the Piston Stem only slides into the receptacle
in the center of the Modulating Plug. The Piston should not bind
and must move up and down easily.
If the Manual Opening Stem 11 has been removed, it must be
re-installed before the Adapter Cover 22 is installed. Insert the
Opening Stem into the opening on the bottom of the Adapter
Cover and push it through the Stem Packing 13 until it is ready to
engage with the threads in the casting. Grasp the Stem at its top
end and pull while, at the same time, turning it counterclockwise
(when viewed from the top of the Stem) to begin to engage the
threads, and, then, complete the turning with a wrench until the
bottom of the stem is about fl ush with the bottom of the Adapter
Cover. Install the Packing Nut 12 at the top of the Stem.
Refrigerating Specialties Division
6
Page 7
Clean the sealing surfaces where the Adapter-to-Body Gasket 5 is
to beinstalled and insert a new Gasket in position, making sure to
line up the hole in the Gasket with the passage “N” hole (see Fig.
1) in the Valve Body 1. The gasket should have a very light fi lm of
refrigerant oil applied to both surfaces before inserting in place.
Position the Adapter Cover 22 so the extension of passage N in
the Adapter lines up with the matching hole in the Valve Body 1.
Insert the bolts (and nuts) and tighten to the torques listed in the
table below. These should be tightened in a pattern that provides
a uniform pull-down of the Adapter Cover to the Valve Body.
Inspect the top surface of the Pilot Seat 44 to be sure that
it is smooth and unblemished. This is essential for reliable
performance and for a tight shut-off. If the surface is not good
replace the Pilot Seat with a new part. There is no gasket or Oring under the Pilot Seat. Tighten the seat to the torque listed in
the table below
Inspect the Diaphragm 45 surfaces to be sure they are clean and
free from scratches, bends or cracks. If range “A” or “V”, there is
only one Diaphragm: if range “D”, there will be two Diaphragms.
Replace any Diaphragms that are defective.
Two Diaphragm Gaskets 43 and 46 are a part of each installation. A
thick, black gasket goes under the Diaphragm 45 against the Valve
Body. and a thin, black gasket goes on top of the Diaphragm. The
Diaphragm(s) is installed bowed toward the Diaphragm Follower
47 and Range Spring 49. That is, the center of the Diaphragm is
higher than its perimeter.
Before installing the Bonnet 51 be sure that the Adjusting Stem
52 is backed out far enough so that when the assembly of Range
Spring 49. Spring Rests 48 and 50, Diaphragm Follower 47 and
Bonnet are put in place, there will be no compression of the
Spring. Place the Diaphragm 45 and both Diaphragm Gaskets 43
and 46 in place on top of the Adapter Cover 22 as described above.
Assemble the Range Spring, Range Spring Rests and Diaphragm
Follower into the Bonnet in the sequence shown in Figs. 1 or
9. This assembly procedure is most convenient if done in the
mechanics hands and not in place on the top of the valve. These
parts can be held in place within the Bonnet as the assembly is
positioned on top of the Adapter at one edge and then slid over to
its proper location. There is no specifi c orientation for the Bonnet.
Insert the Cap Screws 58 and tighten to the torque listed in the
table below. Tighten in a manner that provides a uniform pulldown of the Bonnet.
Check the assembled valve for leaks to atmosphere. Check the
position of the Manual Opening Stem 11 to be as desired. Set the
Range Adjusting Stem 52 to control the pressure as required.
Tighten Stem Packing Nuts 12 and 55 and install Seal Caps 15
and 57.
.
Refrigerating Specialties Division
TABLE OF TORQUES FOR A4W
FASTENERS AND VALVE SEATS
Metric Units U.S. Units
Item mkg ft/lbs
No. (AlI sizes) (AlI sizes)
Valve Seat (2) 13.8 100
Retaining Screw (4) 2.1 15
Bonnet Cap Screws (58) 1.5 11
Adapter Cover Nuts (18) 14.5 105
Pilot Seat (44) 2.8 20
A2D Body Bolt (60) 0.83 -1.1 6 - 8
S6A Body Bolt (42) 0.83 -1.1 6 - 8
Fig. 7-1
7
Page 8
Maintenance and Service
Dirt in the system is the greatest single cause of regulator
malfunction. All screens or fi lters must be cleaned or replaced
when they become dirty. At start up, or when changes or additions
are made, it is especially important that these items are cleaned
or changed frequently. When the RSW companion strainer or
13mm (1/2”) pilot circuit strainer is used, maintain according to
instructions in Bulletin 00-10. Moisture in halocarbon systems,
in particular, can cause corrosion or form ice, causing the
Piston to freeze in position. Filter-driers should be used and
maintained for halocarbon systems.
Before deciding to disassemble a regulator for servicing, the
following investigations should be made:
Check the Manual Opening Stem; it should be turned out
(counterclockwise) for automatic operation.
Check the regulator setting to make sure it is properly
adjusted. Turn Adjusting Screw slowly to see if the regulator
responds. Check regulator pressure range; if wrong, range
spring must be changed or a Vacuum Cartridge installed.
Check other system components for proper operation.
Check hand valves in the system to make sure they are open
or closed as required and the system is receiving liquid or
vapor as the case may be.
Before disassembly of Regulator, make certain that all
refrigerant has been removed (pumped out) from the
regulator and its corresponding Strainer where one is used.
Read Safety Bulletin RSB.
Refrigerating Specialties Division
Fig. 7-2
8
Page 9
TROUBLE SHOOTING SUGGESTIONS
SYMPTOM PROBABLE REASON CORRECTION
Regulator does not
shut off fl ow.
Piston jammed with excess dirt. Remove Piston and clean dirt from Seal Ring and groove.
or damage.
eroded due to fl ash gas. line. For example, reduce rate of liquid overfeed.
Regulator does not Diaphragm ruptured Replace. If Range D make sure two
open. or badly deformed. diaphragms are installed.
or frozen. Install follower carefully.
Regulator Operation
erratic.
diameter or outside diameter is damaged.
thermostats, etc., erratic.
variation, consider using two smaller regulators in parallel. Check
with factory.
Pressure drop across Inlet or outlet restricted. Check for restriction.
regulator too high. Clean strainer.
High pressure drop causes high rate of Increase pipe size at the outlet of the
expansion gas at regulator outlet. regulator.
Regulator does not open all of the way. Check Piston Seal Ring for wear.
Replace and determine cause for wear.
Diaphragm or Pilot Seat dirty, damaged Clean or replace. Clean strainer.
or frozen.
Diaphragm follower stuck or damaged. Clean or replace. Install follower carefully.
Clean bore with crocus cloth. Clean valve and strainer.
Modulating plug leaking due to excess dirt Clean or replace Modulating Plug and or Valve Seat.
Diaphragm and Pilot Seat Replace. Reduce fl ash gas by reducing amount of liquid in suction
Diaphragm Follower stuck, damaged Clean or replace.
Piston Seal Ring worn or torn. Replace Seal Ring. Check for reason.
Diaphragm or Pilot Seat dirty
Clean or replace. Clean strainer.
or damaged.
Diaphragm Follower has dirt on the outside Clean or replace.
Other system components, line controllers, Adjust, repair or replace.
Regulator too far oversized. Check load. Replace with smaller regulator. If load has wide
Regulator too small. Replace with properly sized regulator.
Parts Kits Which Are Exclusive to Each
Port Size Type A4W Regulator
PORT SIZE
Parts Kit Number
and Part Quantities
Item No. Description and Contents 125mm 150mm 200mm
(5”) (6”) (8”)
Seat Kit, Main Valve 201534 201535 201536
2 Seat, Valve 1 1 1
3 O-Ring 1 1 1
4 Screw, Hex Head 1 1 1
5 Gasket 1 1 1
6 Wrench, Seat 1 1 1
Plug Kit, Modulating 201537 201538 201539
7 Plug, Modulating 1 1 1
8 Spring 1 1 1
H Seat Kit, Main Valve 1 1 1
(See Above)
Piston Kit 201540 201541 201542
9 Piston Stem 1 1 1
10 Ring, Seal 1 1 1
5 Gasket 1 1 1
Stem Kit, Opening 201546 201547 201548
11 Stem, Manual Opening 1 1 1
12 Nut, Packing 1 1 1
13 Packing, Stem 1 1 1
14 Washer, Flat 1 1 1
5 Gasket 1 1 1
PORT SIZE
Parts Kit Number
and Part Quantities
Item No. Description and Contents 125mm 150mm 200mm
(5”) (6”) (8”)
Cap Kit, Seal 201549 201550 201551
15 Seal Cap 1 1 1
16 O-Ring 1 1 1
Bolt Kit 201552 201553 201554
17 Bolt, Hex Head 6 10 16
18 Nut 8 12 16
19 Stud 2 2 0
5 Gasket 1 1 1
Gasket Kit 201558 201559 201560
3 O-Ring 1 1 1
5 Gasket 1 1 1
16 O-Ring 1 1 1
45 Gasket 1 1 1
10 Ring, Seal 1 1 1
Adapter/Cover Kit 202861 202484 203099
59 Adapter/Cover 1 1 1
5 Gasket 1 1 1
43 Gasket 1 1 1
21 Plug, Pipe 1 1 1
13 Packing 1 1 1
Refrigerating Specialties Division
9
Page 10
Parts Kits Which Are Common To All A4W Port Sizes
(including A4W, A4WE, A4WS, A4WB, A4WD, A4WP, A4WOE and A4WR)
Item No. Description and Contents Qty. Kit No.
Stem Kit, Adjusting 202120
52 Stem, Adjusting 1
53 Washer, Flat 1
54 Packing, Stem 1
Spring Stem Kit, Range A & V 202006
55 Nut, Packing 1
* Stem Kit, Adjusting (202120) 1
50 Plate, Spring, Upper 1
48 Plate, Spring, Lower 1
49 Spring. Comp. 1
47 Follower, Diaphragm 1
Spring Stem Kit, Range D 202007
55 Nut, Packing 1
* Stem Kit, Adjusting (202120) 1
50 Plate, Spring, Upper 1
48 Plate, Spring, Lower 1
49 Spring, Comp. 1
47 Follower, Diaphragm 1
Bonnet/Spring Kit, Range A & V (A4WOnly) 202008
* Spring Stem Kit (202006) 1
57 Seal Cap 1
56 Gasket 1
51 Bonnet 1
58 Screw, Hex Head** 8
48 Gasket 1
**Not for S, B or D Variations
Bonnet, Spring Kit, Range D (AM Only) 202009
Spring Stem Kit (202007) 1
57 Seal Cap 1
56 Gasket 1
51 Bonnet 1
58 Screw, Hex Head** 8
46 Gasket 1
**Not for S, B or D Variations
Seal Cap Kit 202110
57 Seal Cap 1
56 Gasket 1
Packing Kit, Opening Stem 202101
12 Nut, Packing 1
13 Packing, Stem 1
14 Washer, Flat 1
Spring Kit, Range A & V 202481
50 Plate, Spring, Upper 1
48 Plate, Spring, Lower 1
49 Spring, Comp. 1
46 Gasket 1
Spring Kit, Range D 202482
50 Plate, Spring, Upper 1
48 Plate, Spring, Lower 1
49 Spring, Comp. 1
46 Gasket 1
Diaphragm Kit, Range A & V 200770
45 Diaphragm 1
46 Gasket 1
43 Gasket 1
Diaphragm Kit, Range D 200771
45 Diaphragm 2
46 Gasket 1
43 Gasket 1
Pilot Seat Kit, Range A & D (Not A4WOE) 200411
44 Pilot Seat 1
43 Gasket 1
46 Gasket 1
Seat Kit, Pilot, Range A (Not A4WOE) 202001
44 Seat, Pilot 1
* Diaphragm Kit (200770) 1
Seat Kit, Pilot, Range V (Not A4WOE) 202004
44 Seat, Pilot 1
* Diaphragm Kit (200770) 1
Seat Kit, Pilot, Range D (Not A4WOE) 202003
44 Seat, Pilot 1
* Diaphragm Kit (200771) 1
Bolt Package, A4W Bonnet** 202246
58 Bolts, 5/16”-18 x 7/8” Lg 8
** Not for S, B or D Variations
Item No. Description and Contents Qty. Kit No.
Plug Kit, Pilot, A4WOE 200778
64 Plug, Pilot 1
65 O-Ring 1
66 O-Ring 1
62 Nut, Retainer 1
43 Gasket 1
63 Spring 1
Outlet Regulator Kit 200517
61 Adapter (A4WOE) 1
* Plug Kit, Pilot, A4WOE (200778) 1
68 Screw, Hex Head 8
21 Plug, Pipe 1
Bolt Package, A4WOE Bonnet 202247
68 Bolts, 5/16”- 18 x 1-3/4” Lg. 8
Cover Kit, A4WOE
69 Cover 1
70 Gasket 1
- S, B or D Variations-
Adapter Kit, Series 200564
23 Adapter 1
24 Gasket 2
25 O-Ring 1
26 Insert, Seal 1
21 Plug, Pipe 1
68 Screw 8
Adapter Kit, Seal 202333
24 Gasket 1
25 O-Ring 1
26 Insert, Seal 1
Spacer Kit, Adapt. A2D 202122
Spacer, Adapter (not shown) 1
72 Screw, Hex Hd 4
30 O-Ring 4
Spacer Kit, Adapt. S6A 202123
Spacer, Adapter (not shown) 1
72 Screw, Hex Hd 4
30 O-Ring 4
Tube Kit 201036
37A Nut. Solenoid Tube 1
37B Tube Assembly, Solenoid 1
38 Gasket 1
Bolt/O-Ring Kit 201574
30 O-Ring 2
42 Bolt 4
Plunger Kit, Needle (AC Only) 201019
38 Gasket 1
39 Plunger Needle Assembly 1
Plunger Kit, Needle (DC Only) 201021
38 Gasket 1
39 Plunger Needle Assembly 1
Plunger Seat Kit (AC Only) 201630
38 Gasket 1
39 Plunger Needle Assembly 1
40 Seat Assembly 1
Bolts, A4WD, S, B Bonnet 202247
68 Bolts, 5/16”-18 x 1-3/4” Lg. 8
71 Body, A2D (Not available as a part)
Bolt/O-Ring Kit, A2B Pilot 201572
72 Bolts 4
30 C-Rings 2
- Packages -
Gasket Package/Seal Cap 202408
56 Gasket 12
Gasket Package/Solenoid Kit 202078
38 Gasket 12
Stem Packing Package 202478
54 Packing 25
Plug Package 1/4” NPT 202552
21 Plug 5
O-Ring Package
30 ‘B’-Side, Moduplates; and S6A/A2D/Spacers 12 202424
‘S’-Side, Moduplate (Not illustrated) 6 202425
Refrigerating Specialties Division
10
Page 11
Fig. 9 - S6A Pilot
Refrigerating Specialties Division
Fig. 8
11
Page 12
Fig. 12
A4W
A4WE
A4WP
A4WL
A4WOE
A4WR
A4WB
A4WS
For All Sizes
“e” is 75mm - 3.0 in.
“f” is 100mm -4.0 in.
“g” is 140mm - 5.5 in.
A4WD
Refrigerating Specialties Division
12
Page 13
TABLE OF DIMENSIONS
VALVE VALVE DIMENSION
SIZE VARIATION U L W1 A B C D
mm 125 Common to All mm 114 381 267 190 273
In. 5
In. 17.25*
A4WP, A4WL mm 438* 318
In. 17.25* 12.5
A4WOE mm 463* 305
A4WR mm 414** 305
In. 16.25** 12.0
A4WB, A4WS mm 476* 451 **
In. 18.75* 17.75**
A4WD mm 502* 476**
In. 19.75* 18.75**
mm 150 Common to All mm 152 483 318 254 349
In. 6
A4W, A4WE mm 514*
A4WP, A4WL mm 514* 394
A4WOE mm 539* 381
A4WR mm 489** 381
A4WB, A4WS mm 552* 527**
A4WD mm 578* 552**
mm 200 Common to All mm 197 622 381 356 406
In. 8
A4W, A4WE mm 572*
A4WP, A4WL mm 572* 451
A4WOE mm 597* 438
A4WR mm 546** 438
A4W, A4WE mm 438*
In. 18.25* 12.0
In. 4.5 15.0 10.5 7.5 10.75
In. 6.0 19.0 12.5 10.0 13.75
In. 20.25*
In. 20.25* 15.5
In. 21.25* 15.0
In. 19.25** 15.0
In. 21.75* 20.75**
In. 22.75* 21.75**
In. 7.75 24.5 15.0 14.0 16.0
In. 22.5*
In. 22.5* 17.75
In. 23.5* 17.25
In. 21.5** 17.25
NOTES:
1
Valve body is wider than adapter for 125mm (5”) A4W; Adapter wider than body for 150mm
(6”) & 200mm (8”) A4W
* Allow 75mm (3”) overhead clearance for access to adjusting stem.
** Allow 100mm (4”) overhead clearance for coil or seal cap removal.
Refrigerating Specialties Division
13
Page 14
Warranty
All Refrigerating Specialties Products are warranted against
defect in workmanship and materials for a period of one year
from date of shipment from factory. This warranty is in force
only when products are properly installed, fi eld assembled,
maintained and operated in use and service as specifi cally
stated in Refrigerating Specialties Catalogs or Bulletins for
normal refrigeration applications, unless otherwise approved
in writing by Refrigerating Specialties Division. Defective
products, or parts thereof, returned to the factory with
transportation charges prepaid and found to be defective by
factory inspection will be replaced or repaired at Re frigerating
Specialties’ option, free of charge, F.O.B. factory. Warranty does
not cover products which have been altered or repaired in the
fi eld; damaged in transit, or have suffered accidents, misuse,
or abuse. Prod ucts disabled by dirt or other foreign substances
will not be considered defective.
THE EXPRESS WARRANTY SET FORTH ABOVE CONSTITUTES
THE ONLY WARRANTY APPLICABLE TO REFRIGERATING
SPECIALTIES PRODUCTS, AND IS IN LIEU OF ALL OTHER
WARRANTIES, EX PRESS OR IMPLIED, WRITTEN OR ORAL,
INCLUDING ANY WAR RANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE. No employee, agent,
dealer or other person is authorized to give any warranties
on behalf of Refrigerating Specialties, nor to assume, for
Refrigerating Specialties, any other liability in connection with
any of its products.
Safe Operation (See also Bulletin RSBCV)
People doing any work on a refrigeration system must be
qualifi ed and completely familiar with the system and the
Refrigerating Specialties Division Products involved, or all
other precautions will be meaningless. This includes reading
and understanding pertinent Refrigerating Special ties Division
Product Bulletins, and Safety Bulletin RSB prior to installa tion
or servicing work.
Where cold refrigerant liquid lines are used, it is necessary
that certain precautions be taken to avoid damage which could
result from liquid expansion. Temperature increase in a piping
section full of solid liquid will cause high pressure due to the
expanding liquid which can possibly rupture a gasket, pipe
or valve. All hand valves isolating such sections should be
marked, warning against accidental closing, and must not be
closed until the liquid is removed. Check valves must never be
installed upstream of solenoid valves, or regulators with electric
shut-off, nor should hand valves upstream of solenoid valves or
downstream of check valves be closed until the liquid has been
removed. It is advisable to properly install relief devices in any
section where liquid expansion could take place.
Avoid all piping or control arrangements which might produce
thermal or pressure shock.
For the protection of people and products, all refrigerant must
be removed from the section to be worked on before a valve,
strainer, or other device is opened or removed.
Flanges with ODS connections are not suitable for ammonia
service.
WARNING
FAILURE OR IMPROPER SELECTION OR IMPROPER USE OF
THE PRODUCTS AND/OR SYSTEMS DESCRIBED HEREIN OR
RELATED ITEMS CAN CAUSE DEATH, PERSONAL INJURY AND
PROPERTY DAMAGE.
This document and other information from Parker Hannifi n
Corporation, its subsidiaries and authorized distributors
provide product and/or system options for further investigation
by users having technical expertise. It is important that
you analyze all aspects of your application and review
the information concerning the product or system in the
current product catalog. Due to the variety of operating
conditions and applications for these products or systems,
the user through its own analysis and testing, is solely
responsible for making the fi nal selection of the products and
systems and assuring that all performance, safety and warning
requirements of the application are met.
The products described herein, including without limitation,
product features, specifications, designs, availability and
pricing, are subject to change by Parker Hannifi n Corporation
and its subsidiaries at any time without notice.
Parker Hannifi n Corporation l Refrigerating Specialties Division
2445 South 25th. Avenue l Broadview, IL 60155-3891
Telephone: (708) 681-6300 l Fax: (708) 681-6306
14
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