Safety: Turn off power before adjusting sensors.

Check bin ice level: Confirm that the machine is shutting off while the bin is still low on ice. If the bin is actually full, the code is normal.
Inspect thermostat bulb placement: Ensure the bulb is mounted at the correct height and location per Scotsman specifications (usually near the top of the desired ice level). If it is too low, it will sense cold too early. Reposition and secure it.
Check for air leaks: Inspect the bin door gasket and bin insulation. Cold air leaks can chill the thermostat prematurely. Replace damaged gaskets.
Test thermostat: If the thermostat is accessible, test its open/close temperatures using an ice bath and a thermometer, or compare continuity at room temperature vs. chilled. Replace if it is closing at too warm a temperature.
Control board: If mechanical causes are ruled out, the control board may be misinterpreting the bin signal and may need replacement.

Display shows 'b1' and unit cycles off prematurely

Possible Causes