Hoshizaki MODULAR CRESCENT CUBER SERENITY SERIES KMS-1400MLH Benutzerhandbuch

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IV. Service Diagnosis
A. 10-Minute Diagnostic Procedure
The 10-minute check out procedure is basically a sequence check which can be used 
at unit start-up or for system diagnosis. Using this check out procedure will allow you 
to diagnose electrical system and component failures in approximately 10 minutes 
under normal operating conditions of 70°F (1°C) or warmer air and 50°F (10°C) or 
warmer water temperatures. Before conducting a 10 minute checkout, check for correct 
installation, proper voltage per unit nameplate and adequate water supply. 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 power off and access the icemaker's control box. Clear any ice from the bin 
control actuator located in the bin.
) Turn power on and place the control switch in the "ICE" position. A 5 second delay 
occurs. The red "POWER OK" LED and the green "BC CLOSED" LED on the control 
board come on.  
3) 
One Minute Fill Cycle – LED 4 is on. The fill water valve is energized. After 1 minute, 
the control board checks for a closed lower float switch. If the lower float switch is 
closed, the harvest cycle begins. If closed, continue to step 4. If the lower float switch 
is open, the fill water valve will remain energized through additional 1 minute fill 
cycles until water enters the sump and the lower float switch closes (low water safety 
protection during initial start up and at the end of each harvest). 
Diagnosis: If the fill 
water valve does not open, check for no supply voltage at water valve terminals, bad 
coil, or plugged screen or external filter (no water flow). If the reservoir fills, but the unit 
fails to start harvest, check for open lower float switch (see "II.F.3. Float Switch Check 
Procedure") or bad 1 minute timer in control board. See "II.C.4. Control Board Check 
Procedure."
4) 
Initial Harvest Cycle – LEDs 1, 4 and  are on. The contactor coil energizes to start 
the compressor and fan motors, the hot gas valves energize (also energizing the 
X1 relay), the harvest water valve energizes and the fill water valve de-energizes. The 
harvest water valve is open during harvest for a maximum of 6 minutes or the length of 
harvest minus 50 seconds, whichever is shorter. The pump motor energizes and runs 
for the last 50 seconds of harvest.
  The evaporator warms and the thermistor senses 48°F (9°C). The control board then 
receives the thermistor's 3.9 kΩ signal and turns operation of harvest over to the 
harvest countdown timer. The last 50 seconds of the harvest countdown timer, the 
harvest water valve de-energizes and the water pump energizes, (LED 4 goes off and 
LED 3 comes on). When the harvest countdown timer completes, the freeze cycle 
starts. 
Diagnosis: Check if evaporator is warming up, compressor and fan motors are 
on, hot gas valves are open, harvest water valve open. If these are okay, next check 
for at least 48°F (9°C) on the suction line. If the evaporator is cool, check for inlet 
water too cold or liquid line valves stuck open. If the suction line is at least 48°F (9°C), 
disconnect the thermistor at the white K3 connector on the control board and check for 
resistance of 3.9 kΩ or less. If different, see "II.D. Harvest Control – Thermistor," for 
check procedure. Replace if necessary. If resistance is 3.9 kΩ or less, reconnect the 
thermistor to the white K3 connector on the control board. If harvest does not terminate 
within 3 minutes, replace the control board.