Hoshizaki DCM-271BAH Service Manual page 11

4) Fill Cycle – "WTRIN" LED is on. WV energizes. The 90-sec. low water safety timer
begins. LFS closes. Nothing occurs at this time. The reservoir continues to fill until
UFS closes, terminating the 90-sec. low water safety timer, starting the 30-min. freeze
timer, and de-energizing WV. Diagnosis: Check that "WTRIN" LED turns on and water
fills the reservoir. If not, check for water supply line shut-off valve closed, restricted
water filters, and restricted WV screen. Next, check for 24VAC at CB K2 #8 (O) to
neutral (LBU). If 24VAC is not present, replace CB. If 24VAC is present, turn off the
power switch, disconnect the WV wires and check WV solenoid continuity. If open,
replace WV. Reconnect WV wires, move the power switch to the "ON" position, then
check that DV is not leaking by. Check that WV shuts off when UFS closes.
Note: Low Water Safety– If UFS remains open 90 sec. after WV energizes, a 1-beep
alarm sounds. This alarm resets automatically once UFS closes.
5) Ice Purge Cycle – "GM" LED is on. 5-sec. GM delay timer and 30-min. freeze timer
start. WV de-energizes and "WTRIN" LED turns off. Once the 5-sec. GM delay timer
terminates, GM and CCR energize. CCR cannot energize unless GM circuit is complete
(GM external protector and GM internal protector). Once CCR energizes, CB K9
#5 W/O and CB K9 #6 W/O 5VDC circuit closes and ice purge timer starts (1-min.
"F-A" CB E-0 (H) and later and "F-C" CB dip switch 8 off or 5-min. "F-A" CB E-0 (G)
and earlier dip switch 8 on). See "II.C.3)c. Compressor Control Relay (Ice Purge Timer
Circuit)." If CCR de-energizes, CB K9 #5 W/O and CB K9 #6 W/O circuit opens and an
8-beep alarm occurs. See "III.B. LED Lights and Alarm Safeties." Note: To bypass ice
purge cycle and go straight to freeze cycle, press the "SERVICE" button on CB during
the 5-sec. GM delay time.
Diagnosis CB: Check that UFS closed, WV LED turned off and WV de-energized.
If UFS is closed, "WV" LED is off, and "GM" LED is off, replace CB. If "GM" LED is
on and GM is off, confirm 115VAC at CB K1 #2 (BR) to neutral (W). If 115VAC is not
present, check for loose connection from power switch. If 115VAC is present, check for
115VAC at CB K1 #3 (BK) to neutral (W). If 115VAC is not present, replace CB.
Diagnosis GM: If 115VAC is present at CB K1 #3 (BK) to neutral (W), check GM fuse,
GM capacitor, GM windings, and GM coupling between auger and GM.
Diagnosis CCR: See "II.C.3)c. Compressor Control Relay (Ice Purge Timer Circuit)."
Once ice purge timer terminates (1-min. "F-A" CB E-0 (H) and later and "F-C" CB dip
switch 8 off or 5-min. "F-A" CB E-0 (G) and earlier dip switch 8 on) or the "SERVICE"
button is pressed, freeze cycle begins.
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