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5. To keep the pilot spring case vent from being
plugged or the spring case from collecting moisture,
corrosive chemicals or other foreign material, point
the vent down or otherwise protect it.
6. For proper operation, the Types T208P pilot and
MR95H supply should be installed with the spring
case barrel pointed down as shown in Figure 1.
However, a Type 1290 with a Type T208PL pilot
must be installed with the pilot spring case barrel
pointed up.
7. To remotely vent a Type T208P or T208PL, remove
the vent (key 26) and install tubing or piping into the
1/4 NPT vent tapping. Vent piping should be as short
and direct as possible with a minimum number of
bends and elbows. The remote vent line should have
the largest practical diameter. Provide protection on
a remote vent by installing a screened vent cap into
the remote end of the vent pipe.
8. Refer to Figure 2. Attach a 1/2 NPT upstream
pressure control line to the vessel using a straight
run of pipe. Connect the other end of the control line
to the Type T208P or T208PL pilot. Install a 1/2 NPT
exhaust line between the pilot and vessel.
9. Run a supply pressure line (see Figure 2) to the
Type MR95H regulator inlet (use 3/8 in. / 9.5 mm
outer diameter tubing or 1/4 in. / 6.4 mm pipe
minimum). Type MR95H minimum supply pressure
should be 10 psig / 0.69 bar higher than the set
pressure of the Type MR95H regulator.
Pre-startup Considerations
Before beginning the startup procedures in the next
section, make sure the conditions below are followed:
• Block valves isolate the regulator.
• Hand valves are closed.
• Gauges may be installed (if required) in place of
pipe plugs (key 52, Figure 11).
For proper operation, the Type MR95H
supply pressure regulator is factory set to
the values in the Specifications section.
Startup and Adjustment (Refer to Figure 2)
1. Open valve 'C' to supply the energy source. The
Type MR95H supply regulator has been preset at
the factory according to the control spring in the
pilot. If any field changes have been made, reset the
Type MR95H outlet pressure. See Table 1 for the
correct pressure setting.
Note
2. Open valve 'D' (if used). This valve must have a
large port area and be fully open.
3. Open valve 'E' (if used). This valve must be a full
ported valve that will not restrict pressure registration.
When opening valve 'E' in step 3, the
main valve may go wide-open if the vapor
pressure is higher than the pilot setpoint.
4. Slowly open valve 'A', introducing pressure into the
vapor recovery regulator system.
5. Slowly open valve 'B'. The regulator will go into
immediate operation.
6. The control spring in the Type T208P will be preset
at the factory if setpoint was specified. Otherwise,
the factory setpoint is approximately mid-range of the
spring. The spring range of the pilot is stamped on the
pilot spring case nameplate.
Control spring adjustment may be necessary. To
check the setpoint, raise the vessel pressure while
observing a pressure gauge (manometer) and the
main valve travel indicator to determine whether or
not the setpoint is correct. On a Type T208P, turning
the adjusting screw clockwise into the spring case
increases the pressure setting. On a Type T208PL,
turning the adjusting screw counterclockwise out of the
spring case will increase the pressure setting.
One way to increase the vessel blanketing
pressure temporarily is to manually push
on the blanketing regulator diaphragm.
To push on the diaphragm, remove the
spring case closing cap on the blanketing
regulator (Type T208P or T208PL pilot) and
use a screwdriver or rod to temporarily
push on the diaphragm assembly and
raise the outlet pressure of the blanketing
regulator. Release the manual force on the
diaphragm and the blanketing regulator
will return to its original setpoint.
Shutdown
Installation arrangements may vary but in any
installation, it is important that the upstream block valve
should be closed first and that the upstream valves be
opened or closed slowly.
Type 1290
Note
Note
5
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