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4) Initial Harvest Cycle – LEDs 1, 4, and 2 are on. WV remains energized. Comp, FMR,
and HGV energize. WV is energized during harvest for a maximum of six minutes or
the length of harvest which ever is shorter. LED 4 goes off when WV de-energizes.
CBmonitors the warming of the evaporator via the thermistor located on the suction
line. When the thermistor warms to 48°F (9°C), CB reads a 3.9kΩ signal from the
thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1&
2). The harvest timer has settings of 60, 90, 120, and 180 seconds. For details, see
"II.C.4.b) Harvest Timer (S4 dip switch 1 & 2)." When the harvest timer terminates, the
harvest cycle is complete. CB checks the position of F/S and proceeds to the next cycle
if it is closed, or calls for a 1-minute ll if it is open. The minimum total time allowed by
CB for a complete harvest cycle is 2 minutes.
Diagnosis: Check that WV remains energized, Comp, FMR, and HGV energize.
Average harvest cycle at factory setting is 2 to 3 minutes. How long does initial harvest
last? 1.5 minutes after initial harvest begins, touch the Comp discharge line. Is it hot?
If not, check that Comp is energized, refrigerant pressures are in range, and Comp
is efficient. If it is hot, place a thermometer on the suction line next to the thermistor.
Has it warmed to 48°F (9°C)? If not, check that the HGV is energized and open. On
water-cooled model, check that WRV is not leaking by. If temperature has been reached
and the freeze cycle fails to start, if not yet conrmed, conrm thermistor status. See
"IV.E. Thermistor Check." If the thermistor reading is in proper range and CB fails to
terminate the harvest cycle, CB is bad and must be replaced.
5) Freeze Cycle – LED 1 is on. Comp and FMR remain energized, PM and LLV energize.
WV and HGV de-energize. The unit is held in freeze by a 5-minute short cycle
protection timer (CB will not accept a signal from F/S). After the 5-minute short cycle
protection timer terminates, CB turns freeze termination over to F/S.
Diagnosis: During the rst 5 minutes of freeze, conrm the evaporator temperature
drops. If the evaporator is not cold, conrm that WV and HGV are closed and TXV is
operating properly. Next, check for proper refrigerant pressures, inefficient Comp, or
headmaster sticking (remote air-cooled). After 5 minutes in freeze, disconnect black
F/S connector from CB BLACK K5 connector. If the unit switches out of freeze with
F/S removed, but would previously not switch out of freeze with F/S connected (long
freeze- 3 beep alarm), F/S may be sticking. To check and clean F/S, see "IV.D. Float
Switch Check and Cleaning." If the unit remains in freeze with F/S removed, CB is bad
and must be replaced. See "V.O. Removal and Replacement of Control Board."
Note: Normal freeze cycle will last 20 to 40 minutes depending on model and
conditions. Cycle times and refrigerant pressures should follow performance data
provided in this manual. See "III.C. Performance Data."