Drum won't tumble

After installing the dryer, use Smart Install mode to verify everything works: Press Adjust Time Up + Temp for 7 seconds. Display shows 'SC' (not 'AS' as in some other Samsung models). It tests the moisture sensor (touch sensor) and the motor/heater in two steps. If both pass, display shows 'OK'. If motor or heater fails, display shows 'HE'. This is faster than running a full cycle to verify installation.

Noise from the motor area can be caused by debris (lint, small objects like coins or buttons) stuck on the blower fan wings, creating an imbalance. Remove any alien particles from the fan and check that the fan nut is properly tightened. This is a different problem from blower housing rubbing and does not require fan replacement if the fan itself is undamaged.

Abnormal noise from the heater area can come from two sources: (1) drum back and heater duct movement against the frame — fix by adjusting the contacting surfaces and checking screw fixation, and (2) vibration of the heater heat wire itself — check the fixation points of the heat wire. These are often misdiagnosed as drum or motor problems.

When diagnosing noise coming from the drum area, check not only the support rollers but also the drum itself for cracked welds. A cracked drum weld can produce a rhythmic thumping or scraping noise that may be misdiagnosed as a roller problem. The manual explicitly calls out 'Check if the drum welding is cracked' as a separate step from checking rollers.