Treat burning smells as urgent
If the smell is burning, hot plastic or distinctly electrical, switch the affected unit off using the normal control or isolator only where safe. Do not restart it repeatedly to see whether the smell returns.
Smoke, sparking, heat damage or repeated electrical tripping needs urgent qualified attention. Keep people clear of the equipment and use emergency services where there is an immediate fire risk.
Damp and stale odours need investigation
Moisture is produced during cooling and should drain away. Dirt on accessible filters, contamination within the unit, standing condensate or a drainage problem may contribute to musty odours. Nearby room sources can also be drawn into the airflow.
Follow only the manufacturer-approved homeowner filter instructions. Spraying fragrances or household cleaner into the unit can mask the symptom, damage materials and leave the underlying cause unresolved.
Restore cleanliness and proper operation
A service visit can assess filters, accessible internal cleanliness, drainage and operating condition, then recommend suitable cleaning or repair. The scope depends on the equipment and contamination rather than a generic spray treatment.
Tell Top Local when the smell appears, whether it occurs in cooling or heating, and whether water, poor airflow or unusual noise is also present. These details help distinguish a maintenance issue from a fault.