Page 2 / Bulletin 22-05 A
Port Size
Connection Size
(SW, BW)
Body Size
Kv
Cv
20 mm (3/4”)
3/4”, 1”
1”
10.8
12.6
25 mm (1”)
3/4”, 1”, 1-1/4”
1”, 1-1/4”
12.5
14.6
32 mm (1-1/4”)
1-1/4”, 1-1/2”
1-1/4”, 2”
22.3
26
40 mm (1-1/2”)
1-1/2”, 2”
2”
30
35
50 mm (2”)
1-1/2”, 2”
2”
41.1
48
A4W Port, Connection, and Flow Coeffi cient Table
A4WO Outlet Pressure Regulator Cross Section
(1-1/2” Valve Body Shown)
Seal
Cap
Bonnet
Assembly
Diaphragm
Outlet
Pressure
Passage (N)
Closing
Spring
Modulating
Plug (Piston)
Stainless
Steel Body
Gauge
Port
Aluminum
Port Plate
Adjustment
Stem
Passage (T)
Passage (P)
Inlet Pressure
Passage (N)
Pilot Plug
Description
All A4WO outlet pressure regulators
are pilot operated and require a
minimum of 0.14 bar (2 psig) pressure
drop across the valve to fully open.
Th
e valves are an integrated assembly
of three modules:
A body, which contains the
1.
modulating plug, but is ordered to
suit a particular connection size.
Th
e port size defi nes the size of
the body;
A port plate, which defi nes the
2.
valve function. Control features
can be added by incorporating
pilot solenoids: either an Electric
Shut-Off (S) or a Electric Wide
Open Bypass (B);
Th
e bonnet, which contains the
3.
range set spring and adjustment
stem.
Th
e A4WO is a normally closed valve
furnished with socket weld and weld
neck options only. Th
is unique design
allows the regulator to be welded
into the line without disassembly, yet
provides full access for cleaning and
servicing from the top only.
Th
ese valves will modulate to maintain
a pressure as set for in the fi eld, in
spite of fl uctuations in load, changes
in ambient, changes in available
refrigerant fl ow paths, and other
operating variances. Appropriately
sized, these valves will modulate the
fl ow of liquid or vapor, high side or
low side in a wide variety of system
arrangements. Each port size will
have a specifi c maximum capacity
at full opening corresponding to the
available or sensible-pressure.
Th
e throttle range on this new design
is greatly enhanced, resulting in
optimal performance at low load
conditions. Current regulator designs
can regulate down to 20% of a valves
maximum rating. Th
e A4W series or
regulators can regulate down to 10% of
the valves maximum capacity.
Th
ese valves are generally ordered
with close upstream strainer to
prevent entrance of foreign material
into the valve and the rest of the