Hoshizaki KMD-450MAH Service Manual page 34

and de-energizes PM for 10 seconds. The anti-slush control is deactivated on the
KMD-450MAH and KMD-450MWH. CAUTION! Do not adjust S2 dip switch 6 out
of the factory default position on this model. This dip switch must be left in the
factory default position or this unit will not operate correctly.
Diagnosis: During the first 5 minutes of freeze, confirm that the evaporator
temperature drops. If the evaporator is not cold, check to see if HGV is still open
or if TXV is not opening properly, if WV is continuing to fill the reservoir, if there
are improper unit pressures, an inoperative Comp, or an inoperative HM. Place a
thermometer on the suction line next to the thermistor. When the temperature drops to
36°F (2°C), disconnect F/S (black and red wires) at the 3 -pin connector on the control
box. See Fig. 4. After approximately 5 minutes, the short cycle protection timer expires
and the unit should switch out of the freeze cycle. 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, check
the thermistor for loose attachment or out of spec. For a thermistor check, see "IV.E.
Thermistor Check." If the unit remains in freeze with F/S removed and the thermistor is
properly attached and within spec, replace CB. See "V.N. Removal and Replacement
of Control Board."
Note: Normal freeze cycle will last 20 to 40 minutes depending on model and
conditions. Cycle times and pressures should follow performance data provided
in this manual. See "III.C. Performance Data."
Fig. 4
6) Pump-Out Cycle – (10/20 second pump-out) – LEDs 5, 6, 4, and 7 are on. Comp
and FMR remain energized, HGV energizes, LLV and FM de-energize. DV energizes
after a 2-second delay. PM de-energizes for 2 seconds and then re-energizes, or
de-energizes and stays off depending on the pump-out/drain selector (S2 dip switch 1)
setting. For details, see "II.C.3.g) Pump-Out/Drain Selector (S2 dip switch 1)." When
the pump-out/drain selector is set to pump-out, PM takes water from the tank and
forces it through DV and down the drain. When the pump-out/drain selector is set to
drain, water drains by gravity through DV. CAUTION! Do not adjust S2 dip switch
1 out of the factory default position on this model. This dip switch must be left
in the factory default position or this unit will not operate correctly. Pump-out
lasts 10 or 20 seconds depending on the pump-out timer (S1 dip switch 3 & 4) setting.
When the pump-out timer expires, the pump-out is complete. For details, see "II.C.3.c)
Pump-Out Timer (S1 dip switch 3 & 4)."
Bin Control
Wires
(black)
Float Switch
Connector
(black and red wires)
Thermistor
Connector
(orange wires)
34