E03 — Condenser / Lint Filter Blockage

How to fix it

1. Open the door and remove both lint filters from the door frame — rinse under warm water until fully clean, then air dry.
2. On condenser/heat-pump models, open the lower kickplate and pull out the condenser unit.
3. Rinse the condenser under a faucet from both sides until water runs clear; let it drain fully before reinstalling.
4. Inspect the condenser cavity for stuck lint and wipe out with a damp cloth.
5. On heat-pump models, vacuum the evaporator fins gently with a soft brush attachment.
6. Reinstall all components and close the kickplate firmly until it latches.
7. Run a timed cycle to confirm the code clears and drying time returns to normal.

Why it happens

Typical signs: Cycles take much longer than normal · Clothes still damp at end of cycle · Filter cleaning icon flashing · Dryer overheats or stops mid-cycle

• Lint filter (primary and fine mesh) clogged Fluff buildup restricts airflow through the heat exchanger.
• Condenser unit fouled with lint The slide-out condenser at the bottom needs rinsing periodically — usually every 50-100 cycles.
• Heat exchanger fins blocked Behind the condenser, secondary fins can hold a lint mat that requires rinsing or brushing.
• Evaporator (heat pump models) coated in dust Reduces heat transfer and triggers airflow alarms.
• Blocked air channel between drum and condenser Lint accumulates in the duct over years even with filters cleaned.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

• Bosch dryer lint filter Common replacement
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• Bosch dryer condenser unit Common replacement
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