Manitowoc CVD0675, Technician Manual

Page: 151 / 204

–147–
Cool Vapor Valve Analysis
The valve can fail in two positions:

Valve will not open in the Harvest cycle.

Valve remains open during the Freeze cycle.
Valve will not open in the Harvest cycle
Although the circuit board has initiated a Harvest
cycle, suction and discharge pressures remain
unchanged from the Freeze cycle. The ice machine
will remain in the Harvest cycle for 3.5 minutes (7
minutes QDUAL), then initiate a new Freeze cycle.
After three consecutive Harvest cycles of 3.5 minutes
(7 minutes QDUAL) the ice machine will stop on a
safety limit #2.
Valve remains open in the Freeze cycle
Symptoms of a cool vapor valve remaining partially
open during the Freeze cycle can be similar to
symptoms of an expansion valve, float valve or
compressor problem. Symptoms are dependent on the
amount of leakage in the Freeze cycle.
A small amount of leakage will cause increased freeze
times and an ice fill pattern that is normal.
As the amount of leakage increases, the length of the
Freeze cycle increases and the amount of ice on the
bottom of the evaporator decreases.
A small amount of leakage will cause an audible
indication as the vapor passes through the valve. As
the size of the leak increases, the audible indication
becomes more apparent.
Refer to the Parts Manual for proper valve application.
If replacement is necessary, use only “original”
Manitowoc replacement parts.