Plug Removal & Diaphragm
Replacement
1. Remove all pressure from the line as outlined under
Warning.
2. Remove the compression of the adjusting spring (11)
by rotating the adjusting screw (14) counterclock-
wise.
3. Remove the spring housing (9). Remove spring (11),
spring seat (12) and ball bearing (13).
4. Remove the diaphragm assembly. The diaphragm
assembly consists of the upper diaphragm plate (8),
diaphragm washer (7), washer (6), stem (5) and plug
(4). The plug is attached loosely to the stem. DO
NOT DROP.
5. Secure the upper diaphragm plate in a vise. Use a
wrench on the stem and turn counter-clockwise to
remove.
6. Remove the diaphragm, clean the parts and install
the new diaphragm in reverse order. The radius
edge of the washer goes against the diaphragm.
Clean and degrease the stem threads and apply one
drop of #290 Loctite to them before threading the
stem into the diaphragm plate. When an elastomer
diaphragm is used, thread the parts together hand
tight and then tighten 1/4 turn. When a metal dia-
phragm is used, pull the parts up together tight.
7. Clean the diaphragm seating surfaces on the spring
housing (9) and on the body (1). Remove adjusting
screw (14).
8. Unscrew the cage (2) approximately two turns. Place
the plug, diaphragm assembly, spring, spring seat
and ball bearing back into the valve body. (Metal
diaphragms nest into the counterbore in the body).
Do not lubricate the plug.
9. Install spring housing.
10. Check to see that ball is below the tapped hole for
the adjusting screw and reinstall adjusting screw to
contact ball.
11. Tighten bolts (10) evenly per chart on next page.
12. Thread cage back into the body and pull up snug.
Readjust adjusting screw.
Cage Removal
1. Remove all pressure from the line as outlined under
Warning.
2. Remove the compression of the adjusting spring
(11) by rotating the adjusting screw (14) counter-
clockwise.
3. Turn the hux end on the cage (2) counter-clockwise
and remove it from the body. The o-ring (3) which is
used to seal the cage to the body main remain on
the cage or stay in the body when you remove the
cage.
4. Place the cage in a vise and grip it on the hex to
prevent damage to machined surfaces. The plug will
Start-up Procedure
With the inlet and outlet shut-off valves closed:
1. Throttle the manual bypass valve so that the pres-
sure to be controlled is maintained near the set
point.
2. Slowly open the inlet shut-off valve.
3. Open the outlet shut-off valve.
4. Slowly close the bypass valve, but do not close it
fully until you are certain that the regulator has con-
trol of the system.
5. To change the controlled pressure, turn the adjust-
ing screw clockwise to increase pressure, counter-
clockwise to decrease pressure.
WARNING:
6. Never substitute a longer length adjusting screw.
Personal injury and damage to the valve may result.
Troubleshooting
Erratic Control:
1. Oversizing causes cycling and hunting and reduces
the rangeability of the valve. Make certain that your
sizing is correct.
2. Steam traps downstream may need attention.
3. Safety valve may be jammed open.
4. Excessive foreign matter on seats or plug (4*). Clean
them. Inspect seating surface on plug for deterioration.
5. Valve plug may not be moving freely. Check cage
bore (2).
6. Surges in piping system.
7. Check accumulator.
Will not operate:
1. Diaphragm ruptured. Replace.
2. Adjusting spring broken. Replace.
3. Improper spring setting. Reset.
Maintenance
Warning:
Be sure that there is no pressure in the valve before
loosening any fittings or joints. The following steps are
recommended.
1. Close the inlet shut-off valve.
2. Back off adjusting screw to allow inlet pressure to
open seats.
3. Allow pressure to bleed off through downstream
piping.
4. When inlet pressure gauge indicates no pressure in
the line, close the outlet shut-off valve.
5. Valve may now be removed or serviced.
* Refer to the drawings for the proper orientation of the
parts and for proper nomenclature.
