Evaporator plate ices up excessively with thick frost, and ice harvest becomes unreliable.

Safety: Unplug the unit before defrosting or servicing.

Steps:

• Manual defrost: Allow the unit to sit unplugged with the lid open until all ice and frost melt. Do not use sharp tools to chip ice.
• Descale evaporator: Run a cleaning cycle with ice machine cleaner to remove mineral deposits that interfere with heat transfer.
• Check harvest sensor: Ensure the harvest or defrost sensor is properly attached and not coated with scale. Replace if readings are out of spec.
• Monitor harvest: After restarting, observe whether ice releases cleanly from the evaporator. If not, the hot gas valve or control timing may require professional service.

Note: Frequent overfrosting often indicates underlying sensor or valve issues beyond simple cleaning.