Manitowoc Indigo Series - Self-contained Multiple Expansion Valve Ice Machines - Comparing Evaporator Outlet Temperatures

Part Number Preliminary 6/11 173
Self-contained Multiple Expansion Valve Ice
Machines - Comparing Evaporator Outlet
Temperatures
Comparing the temperatures of the suction lines
leaving the evaporator alone cannot diagnose an ice
machine. However, comparing these temperatures
during the freeze cycle, along with using Manitowoc’s
Freeze Cycle Refrigeration System Operational
Analysis Table, can help diagnose an ice machine
malfunction.
The temperature difference between evaporator
outlets vary throughout the freeze cycle. Compare the
evaporator outlet temperatures to each other during
the last 60 seconds of the freeze cycle. The end of
freeze cycle temperatures vary with ambient and
water temperature, but the temperatures of all
evaporators will always be within 10 degrees of each
other in a correctly operating ice machine. Use this
procedure to document freeze cycle inlet and outlet
temperatures.
1. Use a quality temperature meter, capable of
taking temperature readings on curved copper
lines.
2. Attach the temperature meter sensing device to
the copper lines entering and leaving the
evaporator.
3. Estimate end of freeze cycle and take multiple
readings to assure the comparison was taken in
the last 60 seconds of the freeze cycle.
4. Record the temperatures and compare the
difference.
5. Record the information on the table.
Important
Do not simply insert the sensing device under the
insulation. It must be attached to and reading the
actual temperature of the copper line.