Hoshizaki AM-50BAE-ADDS, AM-50BAE-DS service manual

c)WV Diagnosis: Check that water enters the water tank. If not, check that the water supply line shut‑off valve is open and screens or external filters are clear. Check for 115VAC at CB C2 (BK) to neutral (W) and CB A2 (V) to neutral (W). If 115VAC is not present at CB C2 (BK) to neutral (W), check wiring from BC. If 115VAC is present at CB C2 (BK) to neutral (W) and not at CB A2 (V) to neutral (W), replace CB.

If 115VAC is present and WV does not energize, check WV coil continuity. If open, replace WV.

d)FM and PM Diagnosis: Confirm FM and PM de-energize. If not, check for 115VAC at

CB A1 (LBU) to neutral (W) and CB B1 (P) to neutral (W). If 115VAC is present at CB A1 (LBU) and not at CB B1 (P), CB is still in freeze cycle or CB X1 relay is sticking. Replace as needed.

e)Normal Harvest Cycle Termination Diagnosis: For a thermistor check, see

"II.D. Thermistor Check." If evaporator is warming, thermistor reading is correct, and harvest does not terminate, replace CB.

6) Normal Freeze Cycle. Comp continues. FM and PM energize. HGV and WV de‑energize. CB monitors the cooling of the evaporator via the thermistor located on the evaporator for freeze termination. When the thermistor drops to 27°F (-3°C), CB reads 6.8 kΩ from the thermistor and starts 3-min. FT. 27°F (-3°C) or lower must be maintained the entire 3 min. If reading rises above 27°F (-3°C) before 3-min.

FT terminates, 3-min. FT resets. When 27°F (-3°C) or lower is maintained for 3 min., 5-min. FTT starts.

a)Comp Diagnosis: If Comp de-energizes, check PTC relay continuity. If open, replace PTC. If closed, check Comp external protector and motor winding continuity. Replace as needed. If Comp is energized but evaporator is not cooling, check for an inefficient Comp. See "VIII.B. Performance Data."

b)FM and PM Diagnosis: If FM and PM do not energize, check for 115VAC at CB

B1 (P) to neutral (W) and CB A1 (LBU) to neutral (W). If 115VAC is present at CB

B1 (P) to neutral (W) and not at CB A1 (LBU) to neutral (W), replace CB. If 115VAC is present at CB A1 (LBU) to neutral (W), check FM or PM motor winding continuity, fan blade or PM impeller for binding, and PM capacitor.

c)HGV and WV Diagnosis: Confirm HGV and WV de-energize. If HGV is energized, check for 115VAC at CB B1 (P) to neutral (W). If 115VAC is present after PM energizes, replace CB. If 115VAC is not present and HGV is bypassing, replace

HGV. If WV is energized, check for 115VAC at CB A2 (V) to neutral (W). If 115VAC is present, replace CB. If 115VAC is not present and WV is leaking by, replace WV.

d)Normal Freeze Cycle Termination Diagnosis: 5-min. FTT terminates, harvest cycle starts. If not, check evaporator temperature where thermistor is mounted and check the thermistor. See "II.E. Thermistor Check." If evaporator temperature is below 27°F

(-3°C) for more than 8 min. and freeze does not terminate, replace CB.

7)Shutdown. When the appliance is running, hold ice in contact with the thermostatic bulb. BC switch opens within 10 sec., shutting down the appliance. BC is factory set and generally no adjustment is required. However, adjustment may be needed in some conditions, particularly at higher altitude locations.

Legend: BC–bin control; CB–control board; Comp–compressor; FM–fan motor; FT–freeze timer; FTT–freeze termination timer; HGV–hot gas valve; HT–harvest timer; PM–pump motor; WV–inlet water valve; WVT–inlet water valve timer

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