Hubbell ST, Operating And Maintenance Manual

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11. Convection packages may be equipped with an integral circulator. This
circulator should be serviced per the enclosed pump O&M manual.
12. The unit as well as all strainers should be blown down regularly to remove any
trash, and sediment that may have accumulated.
13. If unit is supplied with anode rod, it shall be inspected for excessive wear.
14. Packing on valves and regulators should be checked for leaks and repaired or
replaced as necessary.
15. To seal the manhole gasket, first install the cover, crab, new gasket, bolt and
nut. Turn the nut until it is snug against the crab, then turn 1 ½
revolutions. Fill
the tank with water and allow pressure to build up, letting the water pressure
seal the gasket. (Some leakage may occur at this point, but as the gasket seats,
leaking will gradually stop). After leaking has stopped, turn the nut
approximately 1 revolution. At this point there may be some miner seepage,
wait a few minutes to see if this seepage stops. If seepage continues drain the
tank, inspect the manhole ring, and cover for any damage, (repair or replace as
required) Repeat the above procedure using a new gasket.
Never try to seal the cover solely by turning the nut down tight this may
cut or crush the gasket and make sealing impossible
.
16. Drain and flush tank as follows. Perform annually or more often , if required.
NOTE: Cement lining is a durable lining that will provide many years of
service protecting your steel pressure vessel from corrosion. The process of
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