Manitowoc Ice S1800 Series, Self-Contained Water-Cooled Cycle Times, Hour Ice Production

Refrigeration System Section 7

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 “OPERATIONAL ANALYSIS TABLE” for the list of data that must be collected for refrigeration diagnostics. This list includes: before beginning service, ice production check, installation/visual inspection, water system checklist, ice formation pattern, safety limits, comparing evaporator inlet/ outlet temperatures, discharge 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.

•Record beginning of freeze cycle suction pressure one minute after water pump energizes.

•Regular cube production derate is 7%

•50Hz production derate is 7%

•50Hz regular cube total production derate is 14%

S1800 SERIES

Self-Contained Water-Cooled

NOTE: These characteristics may vary depending on operating conditions.

Cycle Times

Freeze Time + Harvest Time = Total Cycle Time

Air Temp.		Freeze Time
Around Ice					Harvest
	Water Temperature °F/°C
Machine					Time
	50/10.0		70/21.1	90/32.2
°F/°C
70/21.1	8.5-9.4		9.2-10.1	10.7-11.8
80/26.7	8.5-9.4		9.3-10.3	10.9-12.0	.75-2.00
90/32.2	8.6-9.4		9.4-10.4	11.1-12.2
100/37.8	8.7-9.6		9.6-10.5	11.2-12.3

Times in minutes

24 Hour Ice Production

Air Temp.		Water Temperature °F/°C
Around Ice
Machine	50/10.0		70/21.1		90/32.2
°F/°C
70/21.1	1870		1750		1530
80/26.7	1870		1730		1510
90/32.2	1860		1710		1490
100/37.8	1830		1690		1470
Based on average ice slab weight of 13- 14.125 lb
Condenser
Water		Air Temperature / Water Temperature °F
Consumption
		77/59		90/70	110/90
Gal / per		95		155	510
100 lbs of ice

Water regulating valve set to maintain 240 PSIG discharge pressure

Operating Pressures

Air Temp.	Freeze Cycle		Harvest Cycle
Around Ice	Discharge	Suction	Discharge	Suction
Machine	Pressure	Pressure	Pressure	Pressure
°F/°C	PSIG	PSIG	PSIG	PSIG
50/10.0	225-235	40-24	140-160	60-80
70/21.1	225-275	45-26	155-175	60-85
80/26.7	230-295	45-28	160-180	70-90
90/32.2	255-320	46-29	170-195	80-100
100/37.8	290-360	48-30	190-215	95-115
110/43.3	325-400	49-30	225-250	110-130

Suction pressure drops gradually throughout the freeze cycle

7-20 Part Number 80-1634-3