Hoshizaki F-500BAJ Service Manual page 15

6) Startup–CB "POWER OK" LED is on. Plug the appliance into the electrical outlet
(F-300BAJ) or turn on the power supply (F-500BAJ), then move the power switch to the
"ON" position. Make sure the control switch is in the "ICE" position.
CB "POWER OK" LED turns on.
Diagnosis CB "POWER OK" LED: Check that CB "POWER OK" LED is on. If not,
check for 115VAC at control transformer black (BK) wire to neutral (W). If 115VAC is not
present, check the power switch, power supply cord, and breaker. If 115VAC is present,
check control transformer continuity. Replace as needed. Next, check for 24VAC at
control transformer red (R) wire to neutral (LBU). If 24VAC is not present, check control
transformer continuity. Replace as needed. If 24VAC is present, check 24VAC 1A fuse.
If fuse is good, check for 24VAC at CB K8 #1 (W/R) to CB K8 #2 (LBU). If 24VAC is
present and "POWER OK" LED is off, replace CB.
Diagnosis BC: Check that the actuator paddle is properly positioned. Check continuity
across BC. If open, replace BC. Next, check VDC at CB K8 #3 (GY) to CB K8 #4 (GY).
When BC is closed 0VDC is read. Move the actuator paddle to open BC(2). When open,
5VDC is present between CB K8 #3 (GY) and CB K8 #4 (GY). If 5VDC is not present
when BC is open, replace CB. Return actuator to its normal position.
7) Fill Cycle – "WTRIN" LED is on. Reservoir is empty and LFS and UFS are open.
90-sec. FT starts. WV energizes and fill cycle starts. LFS closes. Nothing occurs at this
time. Reservoir continues to fill until UFS closes. When UFS closes, WV de-energizes,
90-sec. FT is terminated, and CB "WTRIN" LED turns off. 30-min. FZT and 5-sec.
GM delay timer start. If UFS remains open longer than 90 sec. after LFS opens,
FT exceeded and CB sounds a 1-beep alarm. WV remains energized until UFS closes.
Alarm resets automatically when UFS closes. Diagnosis: If reservoir is empty and
"WTRIN" LED is off, confirm LFS status. See "II.E. Float Switch Check and Cleaning."
If LFS is open and "WTRIN" LED is off, replace CB. If "WTRIN" LED is on, check
that the reservoir fills. If not, check water supply line shut-off valve, water filters, and
WV screen. If "WTRIN" LED is on and WV is off, check CB K2 #8 (O) to a neutral
(LBU) for 24VAC. If 24VAC is not present, check CB K2 #9 (W/R) to a neutral (LBU) for
24VAC. If 24VAC is present on CB K2 #9 (W/R) and not on CB K2 #8 (O), replace CB.
If 24VAC is present on CB K2 #8 (O), check continuity through WV solenoid. If open,
replace WV. If WV is energized and refill exceeds FT with no water in the reservoir,
check for DV leaking. If reservoir is full and overflowing check for open UFS. See "II.E
Float Switch Check and Cleaning." If UFS is closed, check that WV de-energizes. If
not, check CB K2 #8 (O) to a neutral (LBU) for 24VAC. If 24VAC is present, replace CB.
If WV de-energizes and water continues to fill the reservoir, replace WV.
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