Hoshizaki KM-1601SAH/3 - Manual (Page 54)

54
IV. Service Diagnosis
WARNING
1. This unit should be diagnosed and repaired only by qualified service
personnel to reduce the risk of death, electric shock, serious injury, or fire.
2. Risk of electric shock. Use extreme caution and exercise safe electrical
practices.
3. Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.
4.
CHOKING HAZARD: Ensure all components, fasteners, and thumbscrews
are securely in place after the unit is serviced. Make sure that none have
fallen into the storage bin.
5. Make sure all food zones in the icemaker and storage bin are clean after
the unit is serviced. For cleaning procedures, see "VI. Cleaning and
Maintenance."
A. Diagnostic Procedure
The diagnostic procedure is basically a sequence check which can be used at unit
startup or for system diagnosis. Before conducting the diagnostic procedure, check
for correct installation, proper voltage per unit nameplate, and adequate water supply.
Check CB using the steps in "IV.B. Control Board Check." Check the dip switch settings
to assure that S4 dip switch 3, 4, 7, 8, 9, 10 and S5 (KM-1601SAH/3 "G" CB) dip switch
1 through 5 are in the factory default position. S4 dip switch 1, 2, 5, 6 are cleaning
adjustments and the settings are flexible. For factory default settings, see "II.C.3.a)
Default Dip Switch Settings." As you go through the procedure, check to assure the
components energize and de-energize correctly. If not, those components and controls
are suspect.
1) Turn off the power supply, then access the control box. Clear any ice from TBC.
2) Turn on the power supply, then move the control switch to the "ICE" position. A
5-second delay occurs. CB red "POWER OK" LED and green "BC CLOSED" LED
(KM-1601SAH/3 "G" CB) turn on. If red "POWER OK" LED is off, clear ice away from
TBC bulb in the storage bin area. If no ice is near TBC bulb or the LED does not turn on
even after clearing away ice, check TBC. See "IV.C. Bin Control Check." If yellow "BC
OPEN" LED (KM-1601SAH/3 "G" CB) is on (indicating a full bin), confirm that CB K4
jumper is in place.
3) 1-Minute Fill Cycle – LED 4 is on. WV and X11 relay (KM-1601SAH/3) energize and
the 1-minute fill cycle begins. After 1 minute, CB checks for a closed F/S. If F/S is
closed, the harvest cycle begins. If closed, continue to step 4. If open, WV remains
energized through additional 1-minute fill cycles until water fills the water tank and
closes F/S (low water safety).
Diagnosis: Confirm that water is filling the water tank. If
not, check that the water supply shut-off valve is open and WV screen and any external
filters are clear. If WV does not energize (LED 4 on), check CB K1 ten-pin connector
pin #6 (O wire) for 115VAC. If no voltage is present, CB is bad and must be replaced.
If voltage is present, check WV connections and solenoid continuity. If unit fails to start
harvest, check for open F/S or bad 1-minute timer in CB. See "IV.D. Float Switch Check
and Cleaning."