Disassembly and Reassembly
Note
User should only disassemble the
controller to replace the Valve Plug
(Disk), change registration from Internal
to External and Spring and Diaphragm
replacement as described below.
all other internal disassembly requires
special tooling and should be done only
at the factory; for example the cam and
reset pin assembly (key 4, Figure 13).
Valve Plug (Disk) Replacement
!
WarNINg
To avoid personal injury or equipment
damage, do not attempt any
maintenance or disassembly without
first isolating the regulator/controller
from system pressure and relieving all
internal pressure.
•
Refer to Figure 13 when following this procedure.
Remove the body flange screws (key 34) and the
two half flanges (key 36). Remove the controller
from the body. If disk replacement is required,
remove the fastening ring (key 44). A specific tool is
required for this, see Table 7.
•
Remove and replace the valve plug (disk)
(key 47, D24 mm medium capacity or D39 mm
high capacity).
•
Replace the fastening ring (key 44).
•
Reassemble in reverse order, taking care to
follow the steps outlined in the General Controller
Reassembly Procedures section.
Changing from Internal to
External Registration
!
WarNINg
To avoid personal injury or equipment
damage, do not attempt any
maintenance or disassembly without
first isolating the regulator/controller
from system pressure and relieving all
internal pressure.
•
Refer to Figure 13 when following this procedure.
Remove the body flange screws (key 34) and the
two half flanges (key 36). Remove the controller
from the body.
•
Install the sense blocking screw (key 51) and
O- ring (key 50).
•
Remove the 1/4 NPT plug from the 1/4 NPT Control
line port (Figure 3).
•
Reassemble in reverse order, ensure to follow
the steps outlined in the General Controller
Reassembly Procedures section.
•
Connect a downstream control line with an outer
diameter of 6.4 mm / 0.25 in. or larger to the 1/4 NPT
Control line port shown in Figure 3 and to the
downstream system as indicated in Figure 5.
Spring and Diaphragm Replacement
•
Refer to Figure 13 when following this procedure.
Unscrew and remove the closing cap (key 3). Using
a flathead screwdriver, unscrew and remove the
OPSO adjusting screw (key 43), OPSO spring
(key 41), maximum washer (key 42).
•
Unscrew and remove the UPSO adjusting screw
(key 40), mini washer (key 103) and UPSO
spring (key 38).
- CLOSE THE UPSTREAM VALVE
- CLOSE THE DOWNSTREAM VALVE
High-Pressure Shutoff
Low-Pressure Shutoff
Supply pressure through outlet purge valve.
Open the purge valve.
Check the value of the shut-off pressure and for any downstream leakage.
Check the value of the shut-off pressure and for any downstream leakage.
Adjust the setpoint, if necessary.
Adjust the setpoint, if necessary.
Table 6.
Flow Chart for Checking Shut-off Mechanism
Systematic Maintenance is Recommended as Specified Below:
VSX4 and VSX8 Series
12
