Zanussi heat pump dryer shows E31 and may stop heating or terminate cycles prematurely.

Safety first: Unplug the dryer before removing any covers. Do not touch live components.

• 1. Locate the moisture sensors: On most Zanussi dryers, two metal sensor bars are located inside the drum near the lint filter opening or on the front bulkhead.
• 2. Clean the sensor bars: Residue from fabric softeners and detergents can insulate the bars. Clean them thoroughly with a soft cloth and a bit of white vinegar or mild detergent. Rinse with a damp cloth and dry.
• 3. Inspect for damage: Check that the bars are not bent, broken, or loose. Ensure there are no visible cracks in the plastic housing around them.
• 4. Check wiring connections: Access the rear or front panel (model dependent) to reach the sensor wiring. Make sure the connectors are firmly attached to the sensor bars and the main harness.
• 5. Continuity test (advanced): With the dryer unplugged, test continuity from the sensor bars to the control board connector using a multimeter. Repair any open circuits or damaged wires.
• 6. Reset and test: After cleaning and checking connections, reassemble the dryer, plug it in, and run a timed cycle. If E31 persists, the sensor itself or the control board input may be faulty.
• 7. Professional help: Replacement of the moisture sensor harness or control board should be done by a qualified technician.