<!-- from fixya rte -->Ice to thick/not harvesting soon enough - Kitchen Appliances - Others

The water runs over the evaporator coil(plate) until the ice gets thick enough, than when the ices touches a switch for the thickness you have it set for, it to go into harvest and the hot gas from the liquid line goes through the evaporator making the ice fall. If you are not making ice, it is the refrigeration system not working, so check the refrigerant, compressor etc like you would on any refrigerator or freezer

There could be so many things wrong with it to cause this problem from just a dirty machine, bad harvest assist plunger, low freon charge, bad hot gas valve. You really need to call a service company.

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?

Remove the ice thickness probe that is hanging at the top of the evaporator plate and clean really good put it back push the freeze tab. If the ice is still getting to thick and not causing the machine to go into a harvest then replace the probe , make sure when you do this to set the thickness by using a 1/8 inch drill bit, lay the bit flat between the evaporator plate and the probe turn the 1/4 screw in or out to achieve the 1/8 inch. The probe is what sets the machine into a harvest, if the ice is not building up enough to cause the water to come into contact whit the probe long enough then it will not go into a harvest. if the ice is getting to thick and the water should be running over the probe it should have went into a harvest if not then the probe is not sensing it to tell the CM3 to go into a harvest.

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.

Replace the ice thickness sensor hanging on the front of the evaporator plate. when you turn the power off and back on factory default is to go to harvest first. if the ice thickness sensor dose not sense the ice is thick enough then it will not go into a harvest. before you replace the sensor take it loose from the evap plate and drop it into the water sump tray if it goes into a harvest then replace the board. if not then replace the sensor.

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?

Likely cause,
1. Ice bridge thickness too small, not enough ice to open curtain.
Solution, Check and adjust if needed.
2.Ice bridge thickness too large, ice frozen to evaporator frame.
Solution, Check and adjust if needed.
3. Purge valve dose not open, water melts ice bridge, not enough ice to open curtain.
Solution, Check purge valve.
4. Incomplete ice formation.
Solution, check water distribution for partially plugged holes.
5. Curtain out of position.
Solution, check curtain for swing restriction.
6. Curtain switch dose not open when curtain does.
Solution, Check switch with ohmmeter.
7. Machine in very cold ambient area.
Solution, Move machine to warmer location.
8. Hot gas valve dose not open.
Solution, Check hot gas valve, check controller using test mode.
9. Harvest assist probe out of position - ejector pin not retracted.
Solution, check harvest assist mechanism-spring should retract pin.
10. Damaged evaporator.
Solution, Check evaporator surface now would be a good time to make sure evaporator plate is not dirty this will cause ice to hang up on evaporator plate also check plate to make sure all cross points are not loose.
11. Fan motor stays on during harvest.
Solution, check controller using test mode.

look for adjustment on the plate . mm