What model scotsman. They make hundreds. Each with it’s own different princeples of operation depending if a cuber, flake, nugget, or block..Â
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Some common things to look for, If air cooled, feel for heat coming out. If you have a good air flow and the air coming out is about 80 to 100 degrees F, the refigerant section is working. Check the drain, is the unit passing water during the freeze cycle?  If so, there is where all the cooling energy is going. As to why, again, model number.
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If it’s only 2 years old, the controller will tell you what is going on.