Vogt HE S Series, Installation & Start-Up Instructions

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Installation & Start-up – HES Series
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Adjustable Blowdown (for clearer ice). A petcock is installed on the overflow from water pump to
provide means for obtaining blowdown from the water tank during the freezing period. This
supplements the blowdown that is discharged during the thawing period through the bypass piping
connected to the drain of the water tank. (See “Automatic Blowdown” below).
The petcock was set at the factory to discharge enough water during the freeze cycle to produce clear
ice for operating conditions. After installation it should be adjusted to the minimum rate required to
maintain production of clear ice and checked after a few days of ice making. See FIGURE-20,
automatic blowdown / petcock
Automatic Blowdown (harvest cycle). A patented feature of this machine is the automatic blowdown
(40), which is provided to eliminate or reduce the necessity for frequent flushing or cleaning of the
water tank (7) to remove accumulated salts or solids in the water as a result of the freezing action.
A principle feature of the blowdown arrangement is a drain by-pass effect which is initiated during
each thawing period when the water pump is stopped and the water in the freezer tubes returns to the
water tank thereby raising the water level higher than the by-pass piping (40) and causing a portion of
the water to drain from the bottom of the tank (approximately 1 gal/cycle).
The water level, controlled by the float valve (12), regulates the quantity of blowdown during the
thawing period. An optional solenoid valve can be furnished in place of the drain valve to permit
additional if required.
FIGURE - 20
Automatic Blowdown / Petcock