Hoshizaki KMD-410MAH, KMD-410MWH manual

a. Lower Float Switch 1st Activation: Refill – The refill can occur at any time during the freeze cycle (1 refill per cycle). As ice builds the water level drops in the reservoir and the lower float switch activates (opens). LED 5 comes on and the control board energizes the fill water valve. The fill water valve remains energized until the upper float switch closes or the 1 minute fill timer terminates, whichever comes first.

b. Lower Float Switch 2nd Activation: The unit is held in freeze by a 5 minute short cycle protection timer which starts after the thermistor temperature reaches 2°C. After the 1st lower float switch activation and refill, ice continues to form and the water level drops in the reservoir. When the lower float switch activates (opens) a second time, the freeze cycle terminates (freeze can only be terminated on the second activation of the lower float switch and after the minimum freeze period). Diagnosis: During the minimum freeze period, confirm that the evaporator temperature drops, compressor, fan motors and pump motor are energized and that the hot gas valves, harvest water valve and fill water valve (except during refill) are de-energized and not bypassing. Make sure the expansion valves are operating properly and, in cold conditions. Make sure that the drain water valve is not leaking by (water flowing down the potable drain). Check for proper unit pressures, or an inoperative compressor. Disconnect the 3-pin float switch connector from the control box. 15 seconds after disconnecting the 3-pin float switch connector, LED 5 comes on and refill begins. Connect the 3-pin float switch connector back on the control box. When the refill is finished (LED 5 goes off), disconnect the 3-pin float switch connector again. If 5 or more minutes have elapsed in the freeze cycle, the unit should switch out of the freeze cycle. After the unit switches out of freeze, reconnect the 3-pin float switch connector to the control box. If the unit remains in freeze with the float switch disconnected, replace the board. To check the float switch, see "II. 5. [c] FLOAT SWITCH CHECK PROCEDURE."

Note: Normal freeze cycle will last 20 to 40 minutes depending on model and conditions. Cycle times and pressures should follow performance data provided in this manual.

6)Drain Cycle – The compressor remains energized, the hot gas valve energizes, the fan motor de-energizes. The drain valve and pump motor energize, allowing water to drain from the tank for 20 seconds. This removes contaminants from the water tank. Diagnosis: If the drain valve does not open, check the circuit. Check for proper voltage. If water does not drain out, check and clean the tubing at the drain valve and then check and clean the valve assembly.

7)Normal Harvest Cycle – same as the initial harvest cycle – Return to step 4.

Note: Unit continues to cycle until bin control is satisfied or power is turned off. (The drain cycle can be adjusted to occur every cycle, or every 2, 5, or 10 cycles. The factory default is every 10 cycles.) The unit always restarts at the 1 minute fill cycle.

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