299H Series
9
(key 36). Turning the adjusting screw clockwise into
the spring case increases the controlled or reduced
pressure setting. Turning the screw counterclockwise
decreases the reduced pressure setting. Always
tighten the locknut (key 35) and replace the closing
cap after making adjustments.
Type VSX-2 Reset
Note
The overpressure and underpressure
trip points can only be reset if the
Type 299HS outlet pressure is between
the overpressure and underpressure
trip points.
Use the following procedure to reset the Type VSX-2:
1. Unscrew the brass resetting knob to open the
equalizing bypass.
2. Pull out the knob until it stops. This resets the
tripping mechanism.
3. Push in and tighten the knob.
Type VSX-2 Trip Adjustment
Note
An adjustment tool is included with the
Type VSX-2 (see Figure 8). Use only
this tool to make adjustments to the
Type VSX-2. To make adjustments, the
overpressure trip spring (key 7, Figure 7)
is found under the outer adjusting screw
and the underpressure trip spring (key 8)
is found under the inner adjusting screw.
Use the following procedure to adjust the Overpressure
Trip Spring:
1. Use the Type VSX adjusting tool to adjust
the overpressure trip spring to its maximum
compression (see Figure 8).
2. If present, adjust the underpressure spring
(using the Type VSX adjusting tool) to its
minimum compression.
3. Backpressure the unit with the desired
overpressure trip pressure.
4. Reduce the overpressure trip spring compression
until the Type VSX-2 trips.
Use the following procedure to adjust the Underpressure
Trip Spring:
1. Use the Type VSX adjusting tool to
adjust the underpressure trip spring to its
minimum compression.
2. Backpressure the unit with the desired
underpressure trip pressure.
3. Increase the underpressure trip spring
compression (using the Type VSX adjusting tool)
until the Type VSX-2 trips.
Shutdown
Installation arrangements may vary, but in any installation
it is important to open and close valves slowly and the
outlet pressure be vented before venting inlet pressure to
prevent damage caused by reverse pressurization of the
regulator. Isolate the regulator from the system. Vent the
downstream pressure; then vent inlet pressure to release
any remaining pressure in the regulator.
Maintenance
Regulator parts are subject to normal wear and must
be inspected periodically and replaced as necessary.
The frequency of inspection and replacement depends
upon the severity of service conditions and upon
applicable codes and government regulations.
Due to the care Regulator Technologies takes in
meeting all manufacturing requirements (heat treating,
dimensional tolerances, etc.), use only replacement parts
manufactured or furnished by Regulator Technologies.
WARNING
!
Avoid personal injury or damage
to property from sudden release
of pressure or uncontrolled gas or
other process fluid. Before starting
to disassemble, carefully release all
pressures according to the Shutdown
procedure. Use gauges to monitor inlet,
loading and outlet pressures while
releasing these pressures.
On reassembly of the regulator, it is recommended
that a good quality pipe thread sealant be applied to
pressure connections and fittings and a good quality
lubricant be applied to all O-rings. Also apply an anti-
seize compound to the adjusting screw threads and
other areas as needed.
