Written by
Adrian Soto Appliance Repair Content SpecialistPublished September 5, 2026Updated October 20, 2026
Error codeC90 / C9 / C9o
ApplianceDryer
Quick answer
C90, C9 and C9o mean the Vent Blockage test found more than nine-tenths of the vent blocked.
Model compatibility: Samsung reuses codes across series and model years, so C90 / C9 / C9o may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.
Plain language
What this code means
C90 (also C9, C9o) is a Vent Blockage test result: over nine-tenths of the vent is blocked.
The worst of the vent results is C90 (shown as C9 or C9o on some displays): over nine-tenths of the vent is clogged. It is produced only by a Vent Blockage test on your Samsung dryer.
Next move
Samsung’s advice is to clean the lint filter and the exhaust vent.
Important safety warning. Do not attempt repairs involving electrical components, gas, water lines, refrigerant or sealed systems. Unplug the appliance if it is safe to reach the outlet, and leave internal diagnostics to a qualified technician.
Seeing this code on your Samsung appliance?
Book a specialist visit for a clear estimate and approval before any repair.
