Symptoms of an uncleaned air conditioner
- Settings and room conditions.
- Restricted airflow or dirty components.
- A technical issue requiring measurements.
Do not automatically assume low refrigerant.
What is really happening
You see them, smell them or pay for them: smell at start-up, dust leaving the louver in the light beam, black spots on the edge, weak airflow, a unit that no longer cools the room like before, dripping water, noise from a blower unbalanced by deposits, a higher electricity bill.
A loaded evaporator loses 5–7% of airflow and makes the fan use up to 10% more energy, and dirty filters add another 5–15%. If you tick two of the symptoms above, the unit needs cleaning, not a 'top-up'.
The evidence
Symptom test: does your unit need sanitising?
What to do
Mechanical pressure cleaning of the evaporator, blower and pan inside a collection cover, then sanitising; filters washed every two weeks; room humidity kept between 40 and 60%; the unit dried on fan mode before winter. No sprays over dirt, no bleach in the unit, no refrigerant "top-ups".
Related threads
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Read also
- Asthma, bronchitis and air conditioning
- The air we breathe at home
- How much more a dirty unit uses
- Air conditioning and small children
- How often to clean and sanitise the air conditioner
The information on this page is educational and based on cited sources; it does not replace medical advice. We do not do repairs, installation or refrigerant circuit work.