Hoshizaki F-300BAF service manual

5)Refill/Low Water Safety Cycle – As ice is produced, the water level in the reservoir drops. As it drops, the upper float switch and lower float switch open. The upper float switch opens first. Nothing occurs at this time. When the lower float switch opens, the refill begins. The water control relay de-energizes, the low water safety circuit opens (terminals 4 and 6 on the water control relay, 3 and 4 on the timer board), a 90 second countdown timer begins on the timer board, and the inlet water valve energizes. The compressor, fan motor and gear motor continue to run. The upper float switch now has 90 seconds to close before the low water safety timer terminates and shuts down the unit. Once the upper float switch closes, the water control relay energizes, the inlet water valve de-energizes and the low water safety 90 second countdown timer terminates. Diagnosis – Check that the water fill begins. If not, check the lower float switch, voltage to the inlet water valve, the water control relay, water supply, filters, and inlet water valve screen.

7)Shutdown – The bin fills and activates the bin control proximity switch. 90 seconds later the compressor and fan motor de-energize, then 60 seconds later the gear motor de-energizes. Diagnosis: Check that the bin control paddle is activated and that

the proximity switch opens. If the compressor and gear motor fail to stop, check the proximity switch and timer board relays.

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