Asco 8551 Series Installation and operating instructions

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 
 

 
 
Service Notice
Except for coil replacement, the Series 8551 are not repairable.
When any performance problems are detected during routine
inspection, replace valve immediately.
or catalog numbers prefixed WT or E , see separate solenoid
installation and maintenance instructions for information on:
Wiring, Solenoid Temperature, Cause of Improper Operation
and Coil Replacement.
DESCRIPTION
        

           
       



         

         
       
See Flow Selection
And Mounting section.
        



APPLICATIONS



 
 
 
 
 
Port Markings: 
 

 







 
OPERATION
IMPORTANT: Minimum operating pressure differential 30 psi;
maximum 150 psi.
Breather unction 3-way (3/2) mode only: 
           

Single Solenoid:       



Solenoid De-energized: 

  
Solenoid Energized:  


















Solenoid De-energized: 


Solenoid Energized: 


 



 
 

Dual Solenoids:       
     
        

  
©   
   





  




 





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 
 

 
 

 
 


        

 



 
 

  

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
 
       
 
IMPORTANT: Minimum on time for each solenoid is 0.3
seconds.
 
Solenoid A Last Energized: 
 
         
 
Solenoid B Last Energized: 

 
 

 
 
 
   

 





Solenoid A Last Energized: 
 
  
Solenoid B Last Energized: 
 
  

 

    



  




Manual Operator
 


   


       
      







 

  
Metering Device with ilter for 1/8 NPT
Connections (Optional eature)

  
        
 
          
        

Metering Device Adjustment:
 
          

      
  
 
IMPORTANT: The steps above provide only a rough
adjustment of the metering device. inal adjustments must be
made with valve fully pressurized in the line of final
application.



    
    

  
INSTALLATION
      
      
  
 
     
      
      

uture Service Considerations

        
  
Temperature Limitations
 
        

  
    


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 
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  
   
         
        
         
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 
 
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  
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
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 


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
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  
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   
  
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











  °°
°°


 °°
°°
  °°
°°

  °°
°°
 °°
 
Positioning
 
low Selection and Mounting (Refer to igure 3)
  
         

 
        
        
        

 

   

     
          
        
        
  
 
Piping
 
 
 

         
 
         
     OPERATION 
 

       
  
 

 
  


 
 
       
 
         
     
 
Wiring
        
       
° "
 
 
 
Solenoid Temperature
        
   

           
      
 
MAINTENANCE
     

     


Preventive Maintenance
•  
 
• 
 

  

 
• 

Causes of Improper Operation
• Incorrect Pressure:  
 
• aulty Control Circuits:     
    click 
  click 
       


• Burned-Out Coil:

 
• Low Voltage:      
 
Coil Replacement
  
  
 
 
 
 
  
    




 


ORDERIN� IN ORMATION OR
ASCO COILS OR REPLACEMENT VALVES


























 









 
      
 


  
  
    