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Refrigerating Specialties Division
1
ISO 9001:2000 CERTIFIED
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.
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
BULLETIN 23-20D
A4W Series
August 2007
Installation, Service and Parts Information
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.
Seal Cap
Manual
Opening
Stem
Power
Piston
Removable Seat
Seal Cap
Adjusting Stem
Range Spring
Diaphragm
Gauge Port
Pilot Seat
Modulating
Plug
Closing
Spring
Fig. 1 - A4W, A4WE
050405