Manitowoc Ice QF2300 Ice Machine Sequence of Operation, Section, QF2200, Prior To Start-Up

Ice Machine Sequence of Operation Section 4

QF2200

PRIOR TO START-UP

When the toggle switch is placed in the “ice” position the following must occur prior to starting an ice making cycle.

A.The bin level probe must be open (bin level light off). If the probe is closed, (bin level light on) when the toggle switch is moved to ICE, the control system waits until the bin level probe opens, (bin level light off) before starting an ice making sequence. If the bin level probe is removed/disconnected the ice machine will not start.

B.The water level probe must be closed (water level light on) to start the compressor. If the water level probe is open, (water level light off) the control system waits until the water level probe closes before starting the compressor.

INITIAL START-UP 1A. Flush

Immediately after placing the toggle switch into ICE, the dump valve solenoid, and gearbox are energized. After

45seconds the dump valve de-energizes.

1B. Water Fill

After 45 seconds the water float valve solenoid is energized.

2. Freeze Cycle

When water contacts the water level probe the compressor and condenser fan motor energize (condenser fan motor is wired through a fan cycling control).

The gear motor, liquid line solenoid, condenser fan motor and water float valve solenoid remain energized as the ice machine makes ice. The water float valve will open and close automatically to maintain the proper water level.

Remote Condensing Unit

2. Freeze

When the refrigerant pressure is high enough, the low- pressure control closes. Closing the low pressure control energizes the contactor coil and the compressor starts.

The compressor increases the refrigerant pressure, the fan cycling control closes and the condenser fan motor starts. The compressor and condenser fan motor remain energized during the entire Freeze Cycle.

AUTOMATIC SHUT-OFF 3A. Ice Run Out

Ice will build up in the bin until it contacts the bin level probe. After ice contacts the bin level probe for 30 continuous seconds the compressor de-energizes. To allow excess ice to run out, the gear motor and the water float valve solenoid remain energized for an additional 4 minutes, then de-energize.

3B. Water Drain

To allow water to drain from the evaporator, the dump valve energizes for 90 seconds, then de-energizes.

An 8-minute lockout starts when the compressor de- energizes. When the ice drops away from the bin level probe the ice machine will begin an initial start-up cycle, provided the “8-minute lockout” has expired.

8 Minute Lockout

An 8 minute lockout starts when the compressor de- energizes. The bin level light will flash until the 8-minute lockout expires.

After the 8 minute lockout expires the bin level light will de-energize.

The 8 minute lockout time can be overridden by moving the ON/OFF/CLEAN toggle switch from ICE to OFF then back to ICE.

FLUSH SEQUENCE IN THE “ICE” POSITION

After the ice machine has run for 100 hours the ice machine will stop making ice and perform a flush sequence. The flush sequence will remove minerals that have settled in the bottom of the evaporator. The entire flush sequence lasts approximately 11 minutes, after which the ice machine automatically resumes ice making and the 100 hour counter in the control board resets to zero.

NOTE: Flake ice machines use an auger to remove ice from the evaporator. Occasional noises (creaks, groans, or pops) are a normal part of the ice making process.

Remote Condensing Unit

3. Automatic Shut-Off

When the refrigerant pressure is low enough to open the low-pressure switch, the contactor coil is de-energized and the compressor and condenser fan motor stop.

4-2 Part No. 80-1214-3