Ice machine harvest two times and shut off - Scotsman Ice Maker 600LB CM3 30inW Commercial Cubed Machine

It is commercial icemaker, you just call for service and claim the cost against your taxes. It may need refrigerant gas. Once the ice is made and it is ready to harvest, the cycle reverses and heat is directed to the grid to drop the ice. Harvest time is set to 3 1/2 minutes, then it trips out.

Ideas here

https://www.google.com/search?q=Scotsman+Prodigy+Plus+max+harvest+time

Service manuals

https://www.google.com/search?q=Scotsman+Prodigy+Plus+service+manual

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Low room temperature - Most Scotsman ice makers won't produce ice when the temperature is below 55 degrees Fahrenheit. Make sure the machine is in a room or setting that is warmer. ... Faulty thermistor - A bad thermistor usually causes the bin to fill with too much ice.

Diagnostic Codes

• 1 - Long freeze time. Shutting down.
• 1 (flashing) - Retrying long freeze cycle.
• 2 - Long harvest time. Shutting down.
• 2 (flashing) - Retrying long harvest cycle.
• 3 - Water filling slowly.
• 4 - High discharging temperature.
• 5 - Failed sump temp sensor.
• 7 - Failed discharge temp sensor.
• 8 - Thin ice from short freeze cycle.
• 8 (flashing) - Retrying short freeze cycle.

The ice machine has a HARVEST TIMER. You can adjust the harvest time, it comes from the factory for 3 minutes. You should not have to adjust it 3 minutes is plenty of time if every thing is working right. If the machine is operating making ice but not falling in storage bin then check these possible cause.
1. ICE may be stuck in the evaporator and the unit is " frozen up "
POSSIBLE SOLUTION: Clean and sanitize.
Possible Cause: Harvest time set too short - timer needs adjustment.
2. Harvest timer bad: replace harvest timer.

Is the machine producing ice thick enough to come off the evaporator plate? the machine will try to harvest 3 times before it locks out on long harvest. Harvest cycle: The compressor and hot gas valve are both powered during the harvest cycle. The fan and pump are off at this time. The machine stays in the harvest cycle until the evaporator thermistor senses 52 DEG F. If the bin is not full, the unit goes into another freeze cycle. I would check the Thermistor

First is the machine making ice ? If it is making ice is it thick enough so the water comes in contact with the ice thickness probe. This has to happen so the machine will know it needs to go into a harvest. You should not have to fores it into a harvest it should be doing it on it on. There is a harvest button on the CM3 controller but when you push it its going into a harvest and when it finishes the harvest it will shut the machine OFF. I really need more info. What is it doing or not doing?

This machine has a cube size control. Which tells the machine when to go into a harvest. there is a harvest switch did you try to force it into a harvest and if you did, did it harvest. depending on ambient temperature from start of freeze cycle to harvest it should be making ice every 15 to 18 minuets and then go into a harvest. so start the ice machine and time it , run it for 18 minuets and force into a harvest. after ice drops check the ice bridge thickness. Bridge thickness should be about 3/16'' the ice dimple must not be DEEPER than 1/16". If this is good then we need to look at what is not working to harvest ice. The cube size control is a reverse - acting thermostat that controls the start of the timed freeze cycle. It must be set properly to prove the correct size cube bridge. When it is closed, an indicator light on the control board will be on. If you force it into a harvest and it harvest the ice with no problems and the ice is at the right thickness then replace the cube size control, but if dose not harvest the ice and you see the ice is at a good thickness and not to thick because if it is to thick it will freeze to every thing and will not drop. SYMPTOM. Unit freezes, but will not try to harvest. POSSIBLE CAUSE: Cube size control will not close; to check: Unplug water pump, switch unit OFF and then ON, in about 2 minutes the timed freeze light on the control board should be ON. PROBABLE FIX: If timed freeze light does not go ON, replace cube size control. SYMPTOM #2: Timed freeze light glows, but after 4 minutes unit dose not power hot gas nor purge valves Then replace control board.

The machine will try to harvest 3 times before it shuts the machine down. Is the ice thick enough to open the curtain door? if the curtain dose not open the magnet switch then the machine dose not know it has harvested the ice and will keep trying to harvest. Is the ice coming off the evaporator plate during harvest or is it hung on the plate? if hanging on the plate then system needs to be cleaned. is the harvest assist plunger working?

Low ice production has multiple causes. First check condensing coil to see if they are dirty and not passing air. This is the most probable cause for low ice production. Next, measure freeze cycle time and harvest time. Freeze time is typically 20 to 30 minutes and harvest time is normally 1.5 to 3 minutes. If freeze time is long (> 35 minutes), first check water valve shuts after reservoir is full. If it does not shut off the water solenoid operated valve needs replaced. Second, find the harvest solenoid operated valve which branches off the compressor discharge and port high temperature gas into evaporator during harvest and see that evaporator side of harvest valve cools down to surrounding temperature in a few minutes 8 - 10 after freeze cycle starts and harvest time stops. If it does not cool off the valve is leaking by its seat and will require a technician to replace. Lastly, if long freeze cycle could be due to low refrigerant and will require and tech to charge properly. Ice machine are critically charged and a tech will know how to charge the right amount. Again, it is possible the metering device is not passing enough refrigerant and a technician can determine this by checking the superheat and subcool. Low subcooling <3 and a high superheat >20 typically indicate an txv (metering devise) needs replaced and will require a tech to replace.

check the cycle time for a batch of ice. should take around 15 minutes to freeze and then you will hear the harvest cycle kick in. If the harvest cycle takes 3 minutes or more that is your problem. You will need to get a hold of NICKEL SAFE ICE MACHINE CLEANER. DO NOT use CLR or any kind of cleaner other than NICKEL SAFE ICE MACHINE CLEANER. If the ice doesn't fall off of the plate in about 90 seconds either the plate is dirty or the nickel plating has come off. There is a failsafe shut down if the unit takes more than 60 minutes to freeze or more than 3 minutes to harvest 3 consecutive times. The cleaning instructions should be inside of one of the covers. If not it's available online.

How long is a freeze cycle on your unit? How big are the cubes that it's dropping? The three beep error indicates that the unit exceeded maximum freeze time.