Hoshizaki DCM-271BAH-OS Service Manual page 22

3) Fill Cycle–"WTRIN" LED is on: "WTRIN" LED turns on only when the reservoir water
level is low enough to open LFS. Diagnosis: Confirm LFS is open. If "WTRIN" LED
is off and LFS is open and the control switch is in the "ICE" position (open), replace
CB. If "WTRIN" LED is on and water is not filling the reservoir, check for 24VAC at
CB K2 connector between pin #8 (O) and neutral (LBU). If the "WTRIN" LED is on
and 24VAC is not present between CB K2 connector pin # 8 (O) and neutral (LBU),
confirm 24VAC at CB K2 connector between pin #7 (W/R) and neutral (LBU). If 24VAC
is present between CB K2 connector pin #7 (W/R) and neutral (LBU) and not between
CB K2 connector pin #8 (O) and neutral (LBU), replace CB.
Connector
K2 (CB input power)
K2 (WV power)
4) Ice Purge Cycle–"GM" LED is on: "GM" LED turns on once UFS closes (reservoir
full). If UFS is closed and "GM" LED is off, replace CB. If "GM" LED is on but GM does
not start, check for 115VAC from CB K1 connector pin #3 (P) to neutral (W).
If 115VAC is not present, confirm 115VAC from CB K1 connector pin #2 (BK) to neutral
(W). If 115VAC is present on CB K1 connector pin #2 (BK) but not on CB K1 connector
pin #3 (P), replace CB. Once GM energizes, CCR energizes and PT (5-min.) starts.
5) Freeze Cycle–"GM" and "COMP" LED are on: PT terminates or press the "SERVICE"
button on CB after the "GM" LED turns on to bypass ice purge cycle. WARNING!
Risk of electric shock. Care should be taken not to touch live terminals. After PT
terminates, "COMP" LED turns on. If not, confirm CCR contacts are closed.
See step "(1)c). Compressor control relay" above. If CCR contacts are closed, replace
CB. If "COMP" LED turns on and Comp does not start, check for 115VAC from the CB
X1 black (BK) wire and red (R) wire to neutral (W). If 115VAC is present on CB X1 black
(BK) wire and not on CB X1 red (R) wire, replace CB. If 115VAC is present on CB X1
red (R) wire and Comp is not energized, CB operation confirmed, check Comp external
overload, start capacitor, start relay, motor windings, locked rotor.
Legend: AM–agitating motor (gear motor this model); BC–bin control; CB–control board;
CCR–compressor control relay; Comp–compressor; CT–control transformer;
DV–drain valve; FM–fan motor; FT–fill timer (90-sec. low water safety);
GM–gear motor; PT–purge timer; LFS–lower float switch; UFS–upper float switch;
WV–inlet water valve
24VAC CB K2 Connector
Pin # (Wire Color) To Neutral (LBU)
Pin #7 (W/R)
To
Pin #8 (O)
22
K8 pin #2 (LBU)
LFS LFS
Open Closed
24VAC 24VAC
0VAC 24VAC