Refrigerating Specialties Division
4
Installation
All regulators are packed for maximum protection. Unpack carefully.
Check the carton to make sure all flanges and other items are
unpacked. Save the enclosed instructions for the installer and eventual
user.
Do not remove the protective coverings from the inlet and outlet of the
regulator until the regulator is ready to be installed. Protect the inside
of the regulator from moisture, dirt and chips before and during
installation. When welded or brazed flange connections are used, all
slag, scale and loose particles should be removed from the flange
interior before the regulator is installed between the flanges. It is
advisable to install a close-coupled companion strainer (RSF) at the
inlet of the regulator to help protect it from any foreign material in the
system.
The A4A series of regulators will give optimum performance if mounted
in a horizontal line in a vertical position with the manual opening stem
on bottom. Where other positions are desired, the factory should be
consulted; please give application and piping details. The regulator
must be installed with the arrow on the valve body pointing in the
direction of the fluid flow for the regulator to function properly. Backward
flow through the regulator is uncontrolled and will vary with the valve
model and the reverse pressure drop encountered. The regulator is
not a check valve.
Tighten the flange bolts and nuts evenly to provide proper seating of
the flange gasket and to avoid damage to gaskets or flanges. (See
Flange Bolt Torque Table, page 16) Avoid using the regulator flange
bolts to stretch or align pipe. Even the heavy duty semisteel body of
an A4A can be distorted, causing the precision parts to bind.
The regulator should be installed in a location where it is easily
accessible for adjustment and maintenance. The location should be
such that the regulator can not be easily damaged by material handling
equipment. When it is necessary to insulate the regulator (and
companion strainer), the insulation should be installed to provide
access to the regulator (and companion strainer) for adjustment and
maintenance. Do not insulate the 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.
Disassembly and Assembly
Refer to the exploded views, Figs. 6 and 7, in this section.
Before disassembling any A4A type regulator, read the information in
this bulletin and Bulletin RSB, Safety Procedures for Refrigerating
Specialties Division Refrigeration Control Valves.
Before a regulator is removed from the line or disassembled in the
line, make sure that all refrigerant has been removed from the regulator,
including the bonnet where applicable, and the close coupled strainer.
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 33A must be turned out (counter clockwise) to make
sure the valve is open.
Fig. 6
Fig. 7
1
2
3
4
5
6
8
9
10
11
12
13
14
15
16
17
18
19
54
50
27
52
53
31
28
29
30
45
32
33
33B
33A
33
46
47
34
35
36
37
38
40
3/4 - 1¼"
41
43
44
42
39
3/4 - 1¼"
18
1
2
3
4
5
6
8
11
9
10
12
13
14
15
16
61
17
19
48
49
62
63
64
65
50
66
50
S6A MODULAR SOLENOID PILOT
(For A4 - Port Sizes 20-100mm
3/4" - 4")
A2D2, A2D MODULAR
PRESSURE PILOT
A2D2 Port Sizes 20-50mm
(3/4" - 2")
A2D Port Sizes 65-100mm
(2½" - 4")
