Manitowoc J-1300, Service Manual

Page: 127 / 165

Section 7 Refrigeration System
7-22
HOW TO USE THE REFRIGERATION
SYSTEM OPERATIONAL ANALYSIS TABLES
General
These tables must be used with charts, checklists and
other references to eliminate refrigeration
components not listed on the tables and external
items and problems which can cause good
refrigeration components to appear defective.
The tables list five different defects that may affect
the ice machine’s operation.
NOTE: There are only four columns listed across the
top. A low-on-charge ice machine and a starving
expansion valve have very similar characteristics and
are listed under the same column.
NOTE: Before starting, see “Before Beginning
Service” on page 7-9 for a few questions to ask when
talking to the ice machine owner.
Procedure
Step1
Complete the “Operation Analysis” column.
Read down the left “Operational Analysis” column.
Perform all procedures and check all information
listed. Each item in this column has supporting
reference material to help analyze each step.
While analyzing each item separately, you may find an
“external problem” causing a good refrigerant
component to appear bad. Correct problems as they
are found.
If the operational problem is found, it is not necessary to
complete the remaining procedures.
Step 2 Enter check marks (
3
) in the small boxes.
Each time the actual findings of an item in the
“Operational Analysis” column matches the
published findings on the table, enter a check mark.
Example: Freeze cycle suction pressure is determined
to be low. Enter a check mark in the “low” box.
Step 3 Add the check marks listed under each
column.
Add the number of check marks listed in each of the
four columns. When completed, there will be four
separate totals.
Note the column number with the highest total and
proceed to “Final Analysis” on the next page.
NOTE: If two columns have matching high numbers,
a procedure was not performed properly and/or
supporting material was not analyzed correctly.