Jordan Valve Mark 5108 Series Back Pressure Regulator - Manual (Page 3)

-3-
7. While observing the inlet pressure gauge ,retard
flow in the system by closing valves or otherwise
reducing demand until the pressure increases to
approximately 5 psi above the desired set point.
8. Slowly turn the adjusting screw of the pressure
relief pilot (2) counterclockwise until the valve
opens and the pressure falls to the set
point. Tighten the adjusting screw jam nut and
replace the plastic cap.
9. Increase flow in the system or otherwise in-
crease demand until pressure returns to normal.
Observe the closing speed of the valve. Ideally,
the valve should close just slow enough
to avoid inducing any secondary surges
in the system. Turn the adjusting screw of the
flow control valve (4) clockwise to
decrease closing speed; counterclockwise to
increase closing speed. CAUTION: Do
NOT adjust the/low control valve fully closed. To
do so can keep the valve from closing at all.
10. Shut down the pump.
Procedure B. Pressure Sustaining Valve
1. Install a pressure gauge of the proper range
upstream of the Mark 5108. The unused inlet
side port in the main valve body may be used
for this purpose if there is no convenient location
in the upstream piping.
2. Remove the plastic cap from the pressure relief
pilot (2) and loosen the adjusting screw jam nut.
Turn the adjusting screw clockwise to a full stop.
3. Loosen the adjusting screw jam nut on the flow
control valve (4) (closing speed control). Turn
the adjusting screw clockwise to a full stop, then
counterclockwise three full turns.
4. Make sure both pilot system isolation ball valves
(6A and 6B) are open.
5. Start the pump or otherwise start the system
flowing. The main valve at this time should be
fully closed.
6. Carefully loosen a pipe plug in the main valve
bonnet until fluid begins to discharge around the
threads. When only clear fluid (no air) is
discharging, retighten the plug.
7. Turn the adjusting screw of the pressure relief
pilot (2) counterclockwise until it is loose enough
to be turned with the fingers. The main
valve should open fully.
8. Observing the inlet pressure gauge, open valves
or otherwise increase flow until the pressure falls
to a point approximately 5 psi below the desired
set point.
M
ark
5108 S
erieS
B
ack
P
reSSure regulating
V
alVe
9. Slowly turn the adjusting screw of the pressure
relief pilot (2) clockwise until the pressure rises
to the set point. Tighten the adjusting screw jam
nut and replace the plastic cap.
10. Shut down the pump.
m
aIntenance
Because of the simplicity of design of the Mark 5108,
required maintenance is minimal. However, the following
checks, periodically performed, can do much to keep
the valve operating properly and efficiently.
1. Check for chipped or peeling paint. Touch up as
required.
2. Check for leaks at fittings and around flanges
and connections. Tighten as required.
3. If the valve is equipped with a Y-strainer, check
the screen for buildup of solid material. Clean as
required. This point is most important, as 1
a clogged strainer can keep the valve
from closing. On new installations, it is
recommended that the strainer be checked
every day or two until experience dictates a
greater or lesser interval. Strainer maintenance
is covered in detail on a special page
later in this manual.
t
roubleshootIng
In the event of malfunction of the Mark 5108, the
following guide should enable the technician to
isolate the specific cause of the problem and take the
appropriate corrective action.
A. Main Valve fails to Open:
1. Valve closed upstream or downstream of the
Mark 5108. Open as required.
2. Downstream pilot system ball valve (6B) closed.
Open as required.
3. Pressure relief pilot (2) adjusted too far clock-
wise. See Adjustment instructions.
4. Diaphragm of pressure relief pilot (2) ruptured.
This will be evidenced by a discharge of
fluid from the vent hole in the pilot bonnet.
Replace diaphragm.
5. Stem of pressure relief pilot (2) binding. Disas-
semble pilot and determine cause.
6. Stem of main valve binding. Disassemble valve
and determine cause.