Bosch Dryer Not Drying Properly - Airflow Mystery Solved

A customer in Armidale called John Crawford Electrical and Air Conditioning with a common issue: their Bosch heat pump dryer was running through full cycles, but the clothes were still coming out damp.

All filters had been cleaned, and the machine appeared to operate normally otherwise. John began with a full diagnostic check, testing all components, including a manual inspection of the compressor. Everything checked out.

The next step was an airflow test – which the machine failed.

After filters, the most likely culprit for restricted airflow in a heat pump dryer is a blocked condenser. This is the critical area where moisture is removed from the air. Although rare, it can become blocked by fine lint. John disassembled the dryer and confirmed the condenser was clean.

The real issue turned out to be much subtler.

While reassembling the dryer, John noticed slight discolouration on the primary filter gauze – a fine mesh that isn’t always easy to inspect. A quick blow test revealed it was indeed restricting airflow. The filter was removed, soaked in a strong detergent, gently scrubbed, and dried.

After reassembly and testing, the dryer was back to full performance, with clothes coming out completely dry.