Section 7Refrigeration System7-22HOW TO USE THE REFRIGERATIONSYSTEM OPERATIONAL ANALYSIS TABLESGeneralThese tables must be used with charts, checklists andother references to eliminate refrigerationcomponents not listed on the tables and externalitems and problems which can cause goodrefrigeration components to appear defective.The tables list five different defects that may affectthe ice machine’s operation.NOTE: There are only four columns listed across thetop. A low-on-charge ice machine and a starvingexpansion valve have very similar characteristics andare listed under the same column.NOTE: Before starting, see “Before BeginningService” on page 7-9 for a few questions to ask whentalking to the ice machine owner.ProcedureStep1 Complete the “Operation Analysis” column.Read down the left “Operational Analysis” column.Perform all procedures and check all informationlisted. Each item in this column has supportingreference material to help analyze each step.While analyzing each item separately, you may find an“external problem” causing a good refrigerantcomponent to appear bad. Correct problems as theyare found.If the operational problem is found, it is not necessary tocomplete 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 thepublished findings on the table, enter a check mark.Example: Freeze cycle suction pressure is determinedto be low. Enter a check mark in the “low” box.Step 3 Add the check marks listed under eachcolumn.Add the number of check marks listed in each of thefour columns. When completed, there will be fourseparate totals.Note the column number with the highest total andproceed to “Final Analysis” on the next page.NOTE: If two columns have matching high numbers,a procedure was not performed properly and/orsupporting material was not analyzed correctly.
