background image

© 2008 Parker Hannifi n Corporation

ISO 9001 CERTIFIED

312068        ECN:  9078        06/11/09

Safe Operation  (See 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 valves involved, or all other 
precautions will be meaningless. Th

  is includes reading and 

understanding pertinent Refrigerating Specialties Division 
Product Bulletins and Safety Bulletin RSB prior to installation 
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.

Warranty

All Refrigerating Specialties products are under warranty 
against defects 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 other-
wise    approved  in  writing  by  the  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 
Refrigerating 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. Products disabled by dirt or other 
foreign substances will not be considered defective.

Th

  e express warranty set forth above constitutes the only 

warranty applicable to Refrigerating Specialties products, and 
is in lieu of all other  warranties, expressed or implied, written 
including any warranty of merchantability, or fi tness for a 
particular purpose.

 

  

In no event is Refrigerating Specialties 

responsible for any consequential damages of any nature what-
soever.  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.

Symptom

Probable Cause

Correction

Failure to open, 
close, or regulate

Piston jammed due to excessive dirt

Flush clearance space between piston and 
cartridge bore with refrigeration oil solvent

Valve Manually Open

Close manual bypass stem by tuning clockwise

Adjusting stem improperly positioned:
a. Turned in too far.  Does not open (inlet regulator)
b. Not turned far enough. Does not close (inlet
    regulator).  Does not open (outlet regulator)

Position adjusting stem properly

Passage “N” clogged

Clean passage “N”

Pilot seat dirty or eroded

Clean and smooth pilot seat. If diaphragm is 
removed, replace with new gasket and O-Ring

Regulator installed backwards

Re-install regulator in proper position

System Control 
cannot  be 
maintained - 
unstable valve 
operation

Improper regulator selection:
a. Actual load is mush lower than regulator capacity
b. Actual pressure drop across valve higher than
    originally intended
c. Combination of a and b

Replace cartridge with one of suitable size

A4W Service Pointers

Location

Description (SAE)

Torque mkg (Ft-Lbs)

Bonnet Screws

M6 x 18 MM

(7)

Port Plate Screws

M10 x 45 MM

(35)

Bonnet Seal Cap

Snug

Solenoid Pseudo 

Assembly

Snug

Gauge Port Plug

1/4” NPT

1.4 (10)

Pilot Plug

7/16-20

Snug

A4W Torque Requirement Table

Summary of Contents for A4W Series

Page 1: ...are its stainless steel and aluminum construction which allows it to withstand corrosive environments and its overall light weight minimizes installation costs Product Features Suitable for Ammonia CO...

Page 2: ...er an Electric Shut Off S or a Electric Wide Open Bypass B The bonnet which contains the 3 range set spring and adjustment stem The A4W is a normally closed valve furnished with socket weld and weld n...

Page 3: ...he presence of system impurities The upward movement of the pilot plug piston causes the pilot plug piston seat to unseat allowing the pressure on top of the piston to vent through the pilot plug pass...

Page 4: ...operation cross section diagram than the standard A4W but the regulating portion of the valve works in the same manner as described in the A4W principles of operation Note The passages in the A4WB po...

Page 5: ...s section shows the B and S solenoid features When both solenoids are de energized there is no flow from the top of the piston and therefore the pressure on top of the piston is equalized to that on t...

Page 6: ...e is then to be backed out approximately 1 16 of an inch before welding Use of welding rings is optional but recommended for butt weld valves They help alignment control gap for full penetration weldi...

Page 7: ...tors with B features can only be adjusted with the pilot solenoid de energized Regulators with the S feature can only be adjusted with the solenoid energized A4W Disassembly See also Bulletin RSBCV Al...

Page 8: ...16 19 20 21 22 23 24 25 26 27 29 31 28 32 30 34 33 23 48 47 46 45 44 35 36 37 38 39 40 41 42 43 A4W Exploded Parts View A4WB shown Note The port plate for a A4W and A4WE inlet pressure regulator does...

Page 9: ...08797 208798 208799 35 39 41 42 Wear Seal Piston 208819 208819 208820 208821 208821 2 5 6 13 14 16 17 20 35 38 41 42 Gasket O Ring A4W A4WK Only 208823 208803 208804 208805 208806 2 5 6 13 14 16 17 20...

Page 10: ...0 mm 3 54 90 0 mm 3 54 90 0 mm 3 54 D 266 7 mm 10 5 299 5 mm 11 79 312 7 mm 12 31 E 41 4 mm 1 63 53 1 mm 2 09 49 3 mm 1 94 A4W Butt Weld BW Dimensions Dimension Port Size 20 25 mm 3 4 1 32 mm 1 1 4 40...

Page 11: ...ating Specialties before proceeding with the work Before doing any service work always be sure to disconnect the power and isolate the valve Failure to do so will result in venting of ammonia Tighten...

Page 12: ...ivision 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 Refrigerating Sp...

Reviews: