Section 7 Refrigeration SystemPart No. 80-1214-3 7-11Cycle Time/24 Hour Ice Production/Refrigerant Pressure ChartsThese charts are used as guidelines to verify correct icemachine operation. Accurate collection of data isessential to obtain the correct diagnosis.• Refer to “Refrigeration System Diagnostics” for thedata that must be collected. This list includes: beforebeginning service, ice production check, installation/visual inspection, water system checklist, iceformation pattern, safety limits, safeguards andsuction pressure analysis.• Ice production checks that are within 10% of thechart are considered normal. This is due to variancesin water and air temperature. Actual temperatureswill seldom match the chart exactly.• Zero out manifold gauge set before obtainingpressure readings to avoid misdiagnosis.• Discharge and suction pressure are highest at thebeginning of the cycle. Suction pressure will dropthroughout the cycle. Verify the pressures are withinthe range indicated.• All pressure readings must be obtained at the icemachine head section. Lineset length will affectpressures at the condensing unit.QF400 SELF-CONTAINED AIR COOLEDNOTE: These characteristics may vary depending onoperating conditions.24 Hour Ice ProductionOperating PressuresAir Temp.EnteringCondenser°F/°CWater Temperature °F/°C50/10.0 70/21.1 90/32.270/ 21.1 395 360 33580/26.7 375 320 30090/32.2 335 300 270100/37.8 295 250 240110/43.3 255 230 225Air Temp. EnteringCondenser °F/°CFreeze CycleDischargePressure PSIGSuctionPressure PSIG50/10.0 160-180 27-2970/21.1 210-235 32-3580/26.7 250-295 34-3990/32.2 285-315 37-41100/37.8 320-360 40-46110/43.3 370-405 44-49Revised 8/2003
