satisfied and stops again. The resultant short-cycling
is easily overcome.
A manual capacity adjustment potentiometer
(“pot”) is provided on the SGH main pc board for that
purpose. It is marked “CAPACITY ADJUST” and is
adjustable from 25 to 100% of rating.
Modulation Control
The SGH humidifier, utilizing modulation control,
does not have the same problems of over sizing. It
reacts to the modulation signal and varies its capacity
automatically. However, if you wish to turn down the
capacity, use the manual capacity adjustment
potentiometer (“pot”).
OTHER POTENTIOMETERS
Do not adjust any other potentiometers (“pots”) on
the pc board(s). They are factory-set and not meant to
be user-set.
DETECTING WATER SUPPLY DEFICIENCY
Knowing how long it normally takes to fill each size
steam cylinder, each humidifier’s pc board is factory
configured to an acceptable maximum filling time. If it
is filling too slowly, when the time expires the
electronics stops the humidifier. To indicate this, the
green light goes out and the yellow light goes on.
REMOTE INDICATION
Every SGH comes factory wired as a set of dry
contacts at 61-20 on the control terminal strip. The
user can connect an indicator externally to 61-20. It
will automatically be activated any time a fault is
detected.
DOUBLE UNIT OPERATION
Turn both switches on. If there is a demand for
humidity, the green status lamp will indicate that the
circuit is operating.
BLOWER PACK OPERATION
Blower packs are equipped with a control
thermostat mounted on the steam distributor. As soon
as humidifier generates steam, the contact is closed
and the fan is started. When steam is no longer being
generated, the fan cuts out with a delay.
If blower packs get overheated (malfunction of the
air circulation), the manual reset safety thermostat
interrupts the steam generation. To reset, switch off
the humidifier and wait until the steam distributor cools
down. Then remove left-hand side intake air filter and,
using a screwdriver, press the reset button (marked
with a red dot) inside the blower packs.
Units are also equipped with speed select switch.
The switch is located on the right-hand side of the
blower, inside the blower pack. To access the switch,
remove right-hand side intake air filter.
To avoid condensation on the cabinet parts, run
blower pack on high speed when humidifier delivers
more than 50 lbs/hr of steam.
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