Hoshizaki KM-901MAH, KM-901MWH, KM-901MRH/3 service manual Off

5)Freeze Cycle – LED 1 is on. Comp and FMR remain energized, PM, LLV, and FM 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 expires, CB turns freeze termination over to F/S. Diagnosis: During the first 5 minutes of freeze, confirm that the evaporator temperature drops. After 5 minutes in freeze, disconnect black F/S connector from CB BLACK K5 connector. 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. The unit should switch out of the freeze cycle ("G" CB - 15 second delay after F/S opens before terminating 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 (longer than 15 seconds on "G" CB)

after disconnecting the black F/S connector, replace CB. See "V.P. 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."

6)Pump-Out Cycle – (10/20 second pump-out) – LEDs 1, 3, and 2 are on. LED 4 is on when S4 dip switch 3 & 4 are set to 3 off and 4 on. Comp and FMR remain energized, HGV energizes. WV energizes if S4 dip switch 3 off and 4 on. LLV and FM de‑energize. PM stops for 2 seconds, then reverses for 10/20 seconds depending on pump‑out timer S4 dip switch 3 & 4 setting. When the pump-out timer expires, the pump-out is complete. The pump-out frequency control is factory set for every 10th cycle, and generally no adjustment is required. However, where water quality is bad and the icemaker needs a pump‑out more often, the pump‑out frequency can be adjusted. The pump-out frequency control (S4 dip switch 5 & 6) can be set to have

a pump-out occur every cycle, or every 2, 5, or 10 cycles. For details, see "II.C.3.d) Pump‑Out Frequency Control (S4 dip switch 5 & 6)."

Timing of the first pump-out is dependent on CB. "E" CB first pump‑out is after the first freeze cycle. "G" CB first pump-out is determined by S4 dip switch 5 & 6. See the table below.

"E" & "G" Control Board Settings			1st Pump-Out
S4 Dip Switch Setting		Pump-Out	"E" Control Board	"G" Control Board
No. 5	No. 6	Frequency
OFF	OFF	Every cycle	After 1st freeze cycle	After 2nd freeze cycle
ON	OFF	Every 2 cycles		After 3rd freeze cycle
OFF	ON	Every 5 cycles		After 6th freeze cycle
ON	ON	Every 10 cycles		After 11th freeze cycle

Diagnosis: If PM does not reverse, check to see if S4 and S5 dip switch settings are in the factory default position. Check PM circuit and capacitor, check #5 pin (DBu wire) on CB K1 ten-pin connector for voltage. If water does not pump out, check and clean the check valve assembly and tubing.

52