Harvest Valve - Koolaire KDT0300A Technician's Handbook

Harvest Valve

General
The harvest valve is an electrically operated valve that
opens when energized, and closes when de-energized.
Normal Operation
The valve is de-energized (closed) during the freeze cycle
and energized (open) during the harvest cycle. The valve is
positioned between the compressor discharge line and the
evaporator and performs two functions:
1. Prevents refrigerant from entering the evaporator
during the freeze cycle.
The harvest valve is not used during the freeze cycle.
The harvest valve is de-energized (closed) preventing
refrigerant flow from the receiver into the evaporator.
2. Allows refrigerant vapor to enter the evaporator in
the harvest cycle.
During the harvest cycle, the harvest valve is
energized (open) allowing refrigerant gas from the
discharge line of the compressor to flow into the
evaporator. The heat is absorbed by the evaporator
and allows release of the ice slab.
Exact pressures vary according to ambient temperature
and ice machine model. Harvest pressures can be found
in the Cycle Time/24 Hour Ice Production/ Refrigerant
Pressure Charts in this book.
Part Number STH063 9/17 71