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The A8 ductile iron-bodied regulators, with brazed copper couplings, maintain a constant pressure at a control point regardless of fluctuations in load, ambient conditions, or alternate diversions for flow.

The A8 has a unique modular design that allows the commercial pressure regulator to be soldered into the line without disassembly, yet provides full access for disassembly, cleaning and servicing from the top only. Interchangeable capacity cartridges facilitate flow revisions should an undersized or oversized condition be created, while pilot adaptors can be changed out to add features or even change functions. Thus, retrofitting for additional evaporator capacity, heat reclaim, or hold back for hot gas defrost is simple and requires no pipe line revisions under most circumstances. These valves will modulate to maintain a pressure as set for in the field, in spite of fluctuations in load, changes in ambient, changes in available refrigerant flow paths, and other operating variances. Appropriately sized, these valves will modulate the flow of liquid or vapor, high side or low side in a wide variety of system arrangements used in industrial, commercial and air conditioning installations. Models are available in combinations of connection sizes, port sizes, functions and features as designated by the model code, for application in a wide variety of control functions on industrial, commercial and air conditioning systems.

Three control functions are available:

Inlet, Outlet, and Differential pressure control. Two control features can be added by incorporating pilot solenoids; either Electric Shut-Off(S) or Electric Bypass (B); also called Wide-Opening.

The valves are an integrated assembly of four modules:

1) A body, which contains no moving parts, but is ordered to suit a particular connection size;

2) A capacity cartridge, which contains both piston and modulating plug, and defines the Port Size;

3) A pilot adapter, which defines the valve function and onto which the Pilot Solenoids providing either the “S” or “B” feature are added as required;

4) The bonnet, containing the Range Spring and adjustment screw, which mechanisms are set for the value of pressure which the valve is to maintain.


• Commercial Refrigeration

Features and Benefits:

• Inlet and outlet functions feature the wide range pressure setting, 250mm Hg to 27.6bar (10” Hg to 400 psig)

• Regulators for differential function have a range of 0 to 8.3 bar (0 to 120 psi)

• Dual spring for wide range pressure set-points

• Pilot operated for close control at desired set-point

• Excellent regulation at light loads

• Interchangeable capacity cartridges (Except for the A82’s)

• Inlet, outlet or differential regulator functions

• Low pressure drop

• Few moving parts

• Long life stainless steel diaphragms

• Variations available for pilot electric shut-off and pilot electric wide open pressure control

• Manual openings feature

• All service from the top

• Sweat-in-place without disassembly


• Industrial Refrigeration

• Commercial Refrigeration

• Air Conditioning

• A particular inlet regulator can be applied to control evaporator, condensate, discharge, or defrost relief pressure

• A particular outlet regulator can be applied to control crankcase, receiver or hot gas bypass

• A differential regulator can be applied to maintain oil receiver pressure, or discharge differential, or liquid line differential pressure


Various Valve Types- Please Configure Part for Specification


9mm to 66mm


3/8″ to 2-5/8″


15mm to 86mm


5/8″ to 3-3/8″


7lbs to 18lbs


250mm Hg to 27.6 bar or 0 to 8.3 bar


10″ Hg to 400 psig, 0 to 120 psig, 0 to 120 psig


Standard, Electric Wide Open, Electric Shut- Off, Electric Shut- Off and Electric Wide Opening


Not Applicable, 110-120VAC ~ 50/60 Hz, 220-240VAC ~ 50/60 Hz, 208VAC ~ 60 HZ


Inlet, Differential, Outlet


Internally Equalized or Externally Equalized