An air conditioner that isn't regularly cleaned can spread mold spores and bacteria throughout your home. This guide covers how to prevent mold in rental AC units, how to clean filters, and the pros and cons of AC-included rental apartments.
Why Cleaning the AC Matters
Dust and moisture accumulate on the filter and internal components, creating ideal conditions for mold. A dirty AC can reduce cooling efficiency by 20–30% and distribute allergens and mold spores into the air.
Cleaning the Filter (DIY)
- Remove the front panel of the AC unit
- Take out the filter(s)
- Vacuum loose dust first
- Rinse with water (from the backside to push dust out) — mild detergent for heavy buildup
- Allow to dry completely before reinserting (never in direct sunlight as it warps the mesh)
Frequency: Every 2 weeks during heavy use (summer/winter).
Preventing Mold in the AC
- Run "dry mode" (ドライ/除湿) for 30 minutes after cooling to dry out internal moisture
- Leave the AC running (fan-only mode) for a few minutes after turning off
- Keep the area around the indoor unit dry and well-ventilated
AC-Included Rentals: Pros and Cons
Pros: No initial cost, no need to choose a model, landlord responsible for major repairs.
Cons: May be an older model, tenant cannot choose preferred brand, must follow usage rules.
FAQ
Q. Who is responsible for deep-cleaning the AC in a rental?
Filter cleaning is the tenant's responsibility. Internal (deep) cleaning is generally the landlord's responsibility, though this may vary — check your lease.
Q. How much does professional AC cleaning cost?
¥8,000–¥15,000 per unit for a standard wall unit by a professional service.
