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critical Hoover
Error Code Ef
Indicates fault in the electronics or software of the dishwashing system leading to improper operation or malfunctioning of control modules.
? What Causes This
Faulty sensor, electronic board failure etc.
✓ How to Fix It
Contact Customer Service for professional repair.
Source: page 14 of the official manual
From the manual
This error code appears in:
Hoover H Wash 500 Washing Machine Instructions