The normal operation of our 3-Way Solenoid Valves is “normally
closed”. What this means is that air does not come out of port “A” until the
solenoid is activated.
This document illustrates how to change our 3-Way Solenoid Valves
to operate as “normally open”. What this means is that air will come out of
port “A” until the solenoid is activated, at which point it will stop.
Position valve as shown with “EA” and “P” facing upwards. Please note that the manual operator (blue in this picture but sometimes red or silver) may or may not be on the top when you begin
Remove solenoid mounting nut. There is a spring washer
under the nut, make sure that is not lost.
Here it is with the solenoid, mounting nut, and spring washer
Remove the two Phillips head screws from the top of the
Gently pull the top assembly (black part) away from the
Remove the two Phillips head screws from the bottom of
the valve body.
Here it is with both the top and bottom removed.
Carefully push the piston through the valve body. Remove
the large spring.
Pull the piston all the way out. It is coated with a thin
layer of lubrication. Try not to touch it too much so that the majority of lubrication
is left in place.
Here it is fully disassembled.
Turn the piston over and insert in the opposite direction.
Insert large spring back into piston.
Re-install bottom using the two Phillips head screws
Re-install the top using the two Phillips head screws.
Important: See that little hole in the valve body (smaller than the screw
hole)? Make sure the similar sized small hole in the black part matches up
Here it is assembled.
Install the spring washer and retaining nut to the
Here is the valve after the modification has been
Your 3-Way Solenoid Valve will now operate as “normally
Please note that the "P" (the port that air from the compressor goes into) will now be changed to the one that is closest to the solenoid and not the one marked "P".
WARNING: HYDRAULIC AND PNEUMATIC POWER SYSTEMS CAN FAIL THROUGH MISUSE, AGE OR MALFUNCTION. THE SYSTEM DESIGNER
IS WARNED TO CONSIDER THE FAILURE MODES OF ALL COMPONENTS USED IN THE DESIGN AND ENGINEERING OF ALL SYSTEMS AND TO PROVIDE ADEQUATE
SAFEGUARDS TO PREVENT PERSONAL INJURY OR DAMAGE TO EQUIPMENT IN THE EVENT OF SUCH FAILURES