Manitowoc Marine Q 1000, Service Technician'S Handbook

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Ice Formation Pattern
Evaporator ice formation pattern analysis is helpful in
ice machine diagnostics.
Analyzing the ice formation pattern alone cannot
diagnose an ice machine malfunction. However, when
this analysis is used along with Manitowoc’s
Refrigeration System Operational Analysis Table, it
can help diagnose an ice machine malfunction.
Any number of problems can cause improper ice
formation.
Example: An ice formation that is “extremely thin on
top” could be caused by a hot water supply, a dump
valve leaking water, a faulty water fill valve, a low
refrigerant charge, etc.
1. Normal Ice Formation
Ice forms across the entire evaporator surface.
At the beginning of the Freeze cycle, it may appear
that more ice is forming on the bottom of the
evaporator than on the top. At the end of the Freeze
cycle, ice formation on the top will be close to, or just a
bit thinner than, ice formation on the bottom. The
dimples in the cubes at the top of the evaporator may
be more pronounced than those on the bottom. This is
normal.
The ice thickness probe must be set to maintain the
ice bridge thickness at approximately 1/8 in. If ice
forms uniformly across the evaporator surface, but
does not reach 1/8 in. in the proper amount of time,
this is still considered normal.
Important
Keep the water curtain in place while checking the
ice formation pattern to ensure no water is lost.