Hoshizaki KM-901MAJ Service Manual page 19

5b) Harvest Pump Timer – LEDs 1, 3, and 2 are on. When the thermistor reaches 48°F
(9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the
harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4). When WV de-energizes,
LED 4 turns off, X11 relay de-energizes and LED 3 turns on. PM energizes. Comp, FM*,
FMR, HGV, and X10 relay continue.
Diagnosis: Place a thermometer on the suction line next to the thermistor. Has it
warmed to 48°F (9°C) or warmer? Confirm thermistor status. See "II.G. Thermistor
Check." If the thermistor reading is in proper range, dip switch 7 is on, and PM does
not energize before harvest terminates, replace CB. If WV continues, check for 115VAC
at CB K1 #6 (O). If 115VAC is present, and LED 4 is off, replace CB. If LED 3 is on
and PM is not energized, check for 115VAC at CB K1 #5 (DBU). If 115VAC is not
present, replace CB. If 115VAC is present and PM is not energized, check for 115VAC
at X10 relay terminal #7 (Y) to neutral (W). If 115VAC is not present, check for 115VAC
at X10 relay terminal #3 (P) to neutral (W) and X10 relay terminal #5 (Y) to neutral (W).
If 115VAC is present on terminal #3 (P) and not on terminal #5 (Y), replace X10 relay.
If 115VAC is present on X10 relay terminal #7 (Y) and PM is not energized, check for
115VAC at X10 relay terminal #4 (R) to neutral (W) and terminal #6 (DBU) to neutral
(W). If 115VAC is present on terminal #6 (DBU) and not on terminal #4 (R), replace
X10 relay. If 115VAC is present on X10 relay terminal #4 (R), check control switch
contact continuity between terminals #4 (R) and #5 (W/R). If contacts are open, replace
control switch. If contacts are closed and 115VAC is present between control switch
terminal #5 (W/R) and neutral (W), check PM capacitor and motor winding continuity.
5c) Initial Harvest Cycle Termination Diagnosis: When the thermistor reaches 48°F
(9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to
the harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4). Check discharge line
temperature. For a thermistor check, see "II.G. Thermistor Check." If 1-min. fill cycle
starts after harvest timer terminates, check that FS is clean and operating properly, see
"II.F. Float Switch Check and Cleaning." If FS is closed, CB proceeds to the next cycle.
If not, replace CB.
Note: The minimum total time allowed by CB for a complete harvest cycle is based on
S5 dip switch 4. Maximum harvest time allowed is 20 min.
NOTICE! S4 dip switch 7 must remain on. Otherwise, PM will not energize during
the last seconds of harvest.
6) Freeze Cycle – LED 1 is on. Comp, FM*, FMR, and PM continue. FM and LLV
energize. HGV and X10 relay de-energize. Appliance is held in freeze by a 5-min. short
cycle protection timer. After 5-min. short cycle protection timer terminates and FS opens,
freeze cycle terminates.
Note: PM power supply switches from CB K1 #5 (DBU) in harvest to K1 #4 (R) in freeze.
Anti-Slush: When anti-slush is enabled (S5 dip switch 5 "ON"), PM de-energizes when
thermistor reaches 36°F (2.2°C) (5.8kΩ) for 10 sec. then, energizes for the remainder of
the freeze cycle.
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