Maintenance - Sentry Sample II Low Pressure Installation, Operation & Maintenance Manual

Startup
1. Ensure the inlet isolation valve is closed.
2. Initiate cooling water flow through the sample cooler by fully opening the inlet
valve (V-4) and outlet valve (V-5). Verify that minimum required cooling water flow is
occurring. If cooling water is untreated, its temperature rise should not exceed 30°F
(17°C) in order to minimize scaling. Be sure that the outlet temperature does not
exceed 140°F (60°C). When necessary, throttle cooling water flow by partially closing
the globe valve on the cooling water outlet line. Any valve on the cooling water inlet
line shall always be fully open.
3. Introduce power to the panel before sample flow is initiated. Allow the controller to
finish the startup routine. The controller enters the manual mode and the Operation
screen is displayed after the startup routine is complete.
4. Setup the necessary control parameters in the controller including flow rates, startup
pressure and blowdown time. Return the controller to the operation screen.
5. Open the inlet isolation valve to introduce sample. The controller begins to display the
inlet pressure.
6. Place the controller in Auto mode for automatic operation or control the system
manually.

Maintenance

Sample Cooler
Coolers require an occasional descaling of the shell side. This can be done chemically or
mechanically. The frequency of this cleaning depends on the hardness level and the outlet
temperature of the cooling water. When the difference between the cooling water inlet
temperature and sample outlet temperature becomes excessive, it is time to descale the
cooler. If the cooler is used in continuous steam service, demineralized cooling water may
be required to avoid frequent descaling.
Disassembly & Reassembly
1. For heavily scaled coolers, disassembly is made easier by first dissolving the scale.
Remove scale by circulating an inhibited sulfamic acid cleaning solution through the
cooling water side.
2. Replace used gaskets with new ones. After reassembly, pressurize shell and visually
inspect for water leaks. Replace gaskets that show visible leaks. Keep spare shell
gaskets on hand for this need.
3. During reassembly, tighten the bolts only enough so that shell side leaking does not
occur. Over tightening ma y cause gasket failure.
Sentry Sample Sentry II 27