CodeRegistry
Brands
  1. Home
  2. Mitsubishi Heavy Industries
  3. Packaged Air Conditioners
  4. Poor Performance Clogging
About·Privacy·Terms

CodeRegistry — Your global library for technical solutions.

For your safety: always follow the equipment manufacturer’s official manuals. CodeRegistry is an independent help site and is not affiliated with the brands listed here.

Poor Performance Clogging

Reduced Cooling/Heating Due to Clogged Air Heat Exchanger — Airflow restriction

Mitsubishi Heavy Industries · Packaged Air Conditioners

What does Poor Performance Clogging mean?

If your air conditioner is not cooling or heating effectively, it could be due to the air heat exchanger being clogged with dust or foreign objects, which restricts crucial airflow.

Common Causes

  • Accumulation of dust and debris on the heat exchanger fins
  • Foreign objects blocking the air intake or outlet of the unit
  • Infrequent air filter cleaning leading to system clogging

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Ensure the air filter is clean; a dirty filter can indirectly cause the heat exchanger to clog.

  2. 2

    Visually inspect the air inflow side of the heat exchanger for any visible dirt or obstructions.

  3. 3

    If visible and safely accessible, carefully clean the accessible parts of the heat exchanger fins with a soft brush or vacuum (ensure power is off).

  4. 4

    If performance does not improve after cleaning, contact a technician as gas leakage or other internal issues might be present.

Browse all codes in this manual (21)
Verified technical data. Last updated: April 2026

Related Faults

Abnormal Compressor NoiseCompressor Making Abnormal Sound or Vibrating — Indicates a serious internal issueAbnormal DisplayAbnormal Display on Electric Component Box/Control Panel — Indicates an electrical issueAbnormal Fan NoiseFan Making Abnormal Sound or Vibrating — Indicates an internal issue
Source: Mitsubishi Heavy Industries Packaged Air Conditioners
Open Manual (Page 21)Search more codes in this manual