Manitowoc Ice QC0700 Ice Maker User Manual


 
Section 7 Refrigeration System
Part No. 80-1214-3 7-11
Cycle Time/24 Hour Ice Production/Refrigerant Pressure Charts
These charts are used as guidelines to verify correct ice
machine operation. Accurate collection of data is
essential to obtain the correct diagnosis.
Refer to “Refrigeration System Diagnostics” for the
data that must be collected. This list includes: before
beginning service, ice production check, installation/
visual inspection, water system checklist, ice
formation pattern, safety limits, safeguards and
suction pressure analysis.
Ice production checks that are within 10% of the
chart are considered normal. This is due to variances
in water and air temperature. Actual temperatures
will seldom match the chart exactly.
Zero out manifold gauge set before obtaining
pressure readings to avoid misdiagnosis.
Discharge and suction pressure are highest at the
beginning of the cycle. Suction pressure will drop
throughout the cycle. Verify the pressures are within
the range indicated.
All pressure readings must be obtained at the ice
machine head section. Lineset length will affect
pressures at the condensing unit.
QF400 SELF-CONTAINED AIR COOLED
NOTE: These characteristics may vary depending on
operating conditions.
24 Hour Ice Production
Operating Pressures
Air Temp.
Entering
Condenser
°F/°C
Water Temperature °F/°C
50/10.0 70/21.1 90/32.2
70/ 21.1 395 360 335
80/26.7 375 320 300
90/32.2 335 300 270
100/37.8 295 250 240
110/43.3 255 230 225
Air Temp. Entering
Condenser °F/°C
Freeze Cycle
Discharge
Pressure PSIG
Suction
Pressure PSIG
50/10.0
160-180 27-29
70/21.1 210-235 32-35
80/26.7 250-295 34-39
90/32.2 285-315 37-41
100/37.8 320-360 40-46
110/43.3 370-405 44-49
Revised 8/2003