Manitowoc Ice S1800 service manual Electrical System Section Water Level Control Circuitry

Electrical System Section 6

Water Level Control Circuitry

WATER LEVEL PROBE LIGHT

The water level probe circuit can be monitored by watching the water level light. The water level light is on when water contacts the probe, and off when no water is in contact with the probe. The water level light functions any time power is applied to the ice machine, regardless of toggle switch position.

During the freeze cycle, the water level probe is set to maintain the proper water level above the water pump housing. The water level is not adjustable. If the water level is incorrect, check the water level probe position. Reposition or replace the probe as necessary.

WATER INLET VALVE SAFETY SHUT-OFF

In the event of a water level probe failure, this feature limits the water inlet valve to a 6-minute on time. Regardless of the water level probe input, the control board automatically shuts off the water inlet valve if it remains on for 6 continuous minutes.

FREEZE CYCLE CIRCUITRY

Manitowoc’s electronic sensing circuit does not rely on float switches or timers to maintain consistent water level control. During the freeze cycle, the water inlet valve energizes (turns on) and de-energizes (turns off) in conjunction with the water level probe located in the water trough.

During the first 45 seconds of the Freeze Cycle:

•The water inlet valve is on when there is no water in contact with the water level probe.

•The water inlet valve turns off after water contacts the water level probe for 3 continuous seconds.

•The water inlet valve will cycle on and off as many times as needed to fill the water trough.

After 45 seconds into the Freeze Cycle:

The water inlet valve will cycle on, and then off one more time to refill the water trough. The water inlet valve is now off for the duration of the freeze sequence.

HARVEST CYCLE CIRCUITRY

The water level probe does not control the water inlet valve during the harvest cycle. During the harvest cycle water purge, the water inlet valve energizes and de- energizes strictly by time. The harvest water purge jumper may be set at 45 seconds (top and center terminals) or 0 seconds (center and bottom terminals). Set the harvest water purge to 0 seconds when reverse osmosis or deionized water is used. Use the factory setting of 45 seconds for all other types of water.

HARVEST WATER PURGE ADJUSTMENT

45SECOND JUMPER POSITION

0SECOND JUMPER POSITION

SV3139

SV3140

6-24 Part Number 80-1634-3