B. Sequence of Operation
The steps in the sequence are as outlined below. This unit utilizes a control board to switch the icemaker components on and off as needed. When power is supplied, the power switch is in the "ON" position, and the control switch is in the "ICE" position, control board "POWER OK" LED and infrared sensor green LED come on. The "POWER OK" LED remains on constantly. If the infrared sensor yellow LED is on or flashing, move ice away from the infrared sensor lens.
This system utilizes a pump-down solenoid valve in the icemaker and a control
low‑pressure switch in the condensing unit to control the operation of the Comp and FMR. This eliminates the need for an electrical connection between the 2 units. When calling for ice, the control board (X1 on control board) energizes the pump‑down solenoid. The low-side refrigerant pressure rises to 29 PSIG, the control low‑pressure switch (located in the condensing unit) closes, energizing the Comp and FMR. When the ice level satisfies the infrared sensor bin control (bin full), the unit goes into the shutdown cycle. The control board de-energizes the pump‑down solenoid valve (X1 on CB). The low-side refrigerant pressure drops (unit pumping down). When the low-side pressure drops to 9 PSIG, the control low-pressure switch opens, de‑energizing Comp and FMR. Control Low-Pressure Switch Settings: Cut-Out: 9 PSIG. Differential: 20 PSIG.
Cut-In: 29 PSIG.
1. Sequence Cycles and Shutdown
a)Fill Cycle
"WTRIN" LED is on. WV energizes and fill cycle begins. 90-second low water safety timer starts. When UF/S closes, WV de‑energizes, and 90-second low water safety timer resets. 30-second GM delay timer starts. If 90-second low water safety timer terminates before UF/S closes, WV remains energized, and a 1-beep alarm sounds.
b)Ice Purge Cycle
"GM" LED is on. 30-second GM delay timer terminates. GMR (X2 on CB), GM, GMPR, and EH energize. 5-minute ice purge timer starts: GM runs for 5 minutes to clear any ice from the evaporator. To bypass, press the "SERVICE" button on CB after GM starts.
WARNING! Risk of electric shock. Care should be taken not to touch live terminals. Note: UF/S must be closed before GMR will energize.
c)Freeze Cycle
"COMP" and "GM" LEDs are on. 5-minute ice purge timer terminates. GMR (X2 on CB), GM, GMPR, and EH continue. CR (X1 on CB) and PDS energize. When CLPS (in SRC) closes, MC energizes, allowing Comp and FMR to energize. CCH de-energizes. As water in the evaporator cools, ice starts forming within 4 to 6 minutes. This time frame depends on the inlet water and ambient temperature conditions. UF/S and LF/S operate WV as needed to continue the ice making process. This continues until IS activates allowing CB to de-energize X1 on CB and PDS. The unit goes into pump-down, CLPS opens, MC de‑energizes, de‑energizing Comp and FMR. CCH energizes.