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STEAM INJECTION INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
Humidifier start-up and shut-down
OPERATION
HUMIDIFIER START-UP
1. Open steam jacketing shut-off valve, if applicable.
2. Inspect steam valve for proper operation.
Pneumatic: Inspect to ensure that: (1) the valve closes off
steam tight, (2) the stem packing is not leaking steam,
and (3) the diaphragm in the actuator is not leaking air.
Electric: Inspect to be sure the valve operates freely,
closes off steam tightly, and that the stem packing is not
leaking.
3. Inspect steam traps and verify all are working properly.
A blocked steam trap will be cold. A “blowing” steam
trap will be hot and noisy, and the discharge pipe will
be hot for a continuous distance up to 30' (9 m). A
properly operating steam trap will have about a two-
degree temperature drop measured across the trap from
inlet to discharge.
4. Verify airflow proving switch and high limit humidistat, if
applicable, are working properly.
HUMIDIFIER SHUT-DOWN
Close humidifier steam supply shut-off valve.
See “Maintenance procedures” on Page 54.