Refrigeration System Operational Analysis Table; Dual Txv - Manitowoc Marine Q 1800 Service Manual

Refrigeration System
This table must be used with charts, checklists and other references to eliminate refrigeration components not listed on the table
and external items and problems which can cause good refrigeration components to appear defective.
Operational Analysis
(listed below)
Ice Production
Safety limits
Refer to "Analyzing
Safety Limits" to
eliminate problems
and/or components not
listed on this table
Ice Formation Pattern
Left side_______________
_______________________
Right side______________
_______________________
Wait 5 minutes into the
freeze cycle.
Compare temperatures
of compressor discharge
line and both hot gas
valve inlets.
Comp. Disc. ______ °F
Left gas inlet ______ °F
Right gas inlet ______ °F
Freeze cycle
DISCHARGE pressure
_______ _______ _______
1 minute Middle End
into cycle
Freeze cycle
SUCTION pressure
________ _______ _______
Beginning Middle End
Miscellaneous
Enter items in proper boxes.
Final Analysis
Enter total number of
boxes checked in each
column.
MANITOWOC ICE, INC.
2110 South 26th Street P.O. Box 1720 Manitowoc, WI 54221-1720
Phone: (920) 682-0161
42
Q Model Dual Expansion Valve

Refrigeration System Operational Analysis Table

1
Published 24 hour ice production
Calculated (actual) ice production _____________
NOTE: The ice machine is operating properly if the ice production
and ice formation pattern is normal
Stops on safety limit:
1
Ice formation is
extremely thin on top
of one side of
evaporator
-or-
No ice formation on
one side of
evaporator
One hot gas valve
inlet is Hot
-and-
approaches the
temperature of a Hot
compressor discharge
line.
If discharge pressure is High or Low refer to a freeze cycle high or low discharge pressure problem
checklist to eliminate problems and/or components not listed on this table before proceeding.
If suction pressure is High or Low refer to a freeze cycle high or low suction pressure problem
checklist to eliminate problems and/or components not listed on this table before proceeding.
Suction pressure is
High
Hot gas valve leaking
Service Fax: (920) 683-7585
2
_____________
Stops on safety limit: Stops on safety limit:
1
Ice formation is Ice formation normal
extremely thin on top
of one or both sides of
evaporator
-or- bottom of one side of
No ice formation on
entire evaporator
No ice formation on
Both hot gas valve Both hot gas valve
inlets are cool enough inlets are cool enough
to hold hand on
-and-
the compressor
discharge line is Hot. discharge line is cool
Suction pressure is Suction pressure is
Low
Low on charge
-or-
TXV Starving
Web Site - www.manitowocice.com
3
Stops on safety limit:
1 or 2
Ice formation normal
-or-
Ice formation is No ice formation on
extremely thin on entire evaporator
evaporator
-or-
entire evaporator
Both hot gas valve
inlets are cool enough
to hold hand on to hold hand on
-and-
the compressor the compressor
discharge line is Hot.
enough
to hold hand on.
Suction pressure is
High
TXV Flooding
4
1
-or-
-and-
High
Compressor