Hoshizaki Condensing Unit Models SRK-14J/3 B. Sequence of Operation, Sequence Cycles and Shutdown

B. Sequence of Operation

1. Sequence Cycles and Shutdown

The steps in the sequence are as outlined below. When power is supplied, the red "POWER OK" LED and the green "BC CLOSED" LED on the CB turn on (If yellow "BC OPEN" LED is on, the icemaker will not start. In this case clear ice away from BC actuator paddle in the storage bin area). A 5-second delay occurs at startup. Note that the order of the green sequence LEDs from the outer edge of the board is 1, 4, 3, 2.

a)1-Minute Fill Cycle

LED 4 is on. WV1 opens and the fill period begins. After 1-minute, CB checks for closed F/S. If F/S is closed, the harvest cycle begins. If not, WV1 will remain energized through additional 1-minute cycles until water enters the water tank and F/S closes. This serves as a low water safety to protect the water pump.

b)Initial Harvest Cycle

LEDs 1, 4 and 2 are on. Comp, FMRs, HGVs, X10 relay, WV2, X12 relay, and X13 relay energize. WV1 de‑energizes. CB monitors the warming of the evaporator via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the adjustable harvest timer (S4 dip switch 1 & 2). The harvest timer has settings of 60, 90, 120, and 180 seconds. The pump‑out timer (S4 dip switch 3 & 4) acts in place of the harvest timer during cycles with a pump-out (S4 dip switch 5 & 6). WV2 and X12 relay are energized during harvest for a maximum of 6 minutes or the length of harvest minus 50 seconds, whichever is shorter. 50 seconds before the harvest timer terminates, harvest pump timer starts. LED 4 turns off, WV2 and X12 relay de‑energize.

Harvest Pump Timer: LEDs 1, 3, and 2 are on. Comp, FMRs, HGVs, X10 relay, and

X13 relay continue. LED 4 turns off, WV2 and X12 relay de-energize. LED 3 turns on and X11 relay energizes, allowing PM to energize for the last 50 seconds of harvest. NOTICE!

S4 dip switch 7 must remain in the factory default position of 7 on. Otherwise, PM will not energize during the last 50 seconds of harvest. The minimum total time allowed by CB for a complete harvest cycle is 2 minutes. At the end of harvest, CB checks position of F/S and proceeds to the freeze cycle if it is closed or calls for a 1-minute fill if it is open.

c)Freeze Cycle

LED 1 and LED 4 are on. Comp, FMRs, and PM remain energized. LLVs energize. WV1 and LED 4 energize for 1 min. HGVs, X10, X11, and X13 relays de-energize. For the first 5 minutes, CB will not terminate the freeze cycle. At the end of 5 minutes, F/S assumes control of the freeze cycle. As ice builds on the evaporator, the water level in the water tank lowers. Freeze continues until F/S opens, provided the 5-minute minimum freeze timer has terminated.

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