6 min read · 28 December 2025
What Size Air Conditioner Do You Need? Bali BTU Sizing Guide
Why most Bali ACs are undersized — and how to size a unit properly for villa bedrooms, open-plan living rooms and beach-club terraces.
By I Made Suarjana, Lead Technician
Quick sizing table for Bali
| Room | Capacity | PK | BTU | Typical area |
|---|---|---|---|---|
| Small bedroom | 0.5 PK | 5,000 BTU | up to 10m² | rare in villas |
| Bedroom | 1 PK | 9,000 BTU | up to 18m² | most master bedrooms |
| Large bedroom / small living | 1.5 PK | 12,000 BTU | up to 25m² | living rooms, large suites |
| Living room / open-plan | 2 PK | 18,000 BTU | up to 35m² | open-plan villa lounges |
| Restaurant / large lounge | 2.5 PK | 24,000 BTU | up to 45m² | cassette territory |
| Big space / beach-club deck | 5 PK | 48,000 BTU | up to 90m² | dual cassette setup |
The Bali rule of thumb
600 BTU per m² for bedrooms. 700 BTU per m² for living rooms with high ceilings, west-facing glass or open-plan kitchens.
That's about 30% higher than the typical Australian or European rule. Why? Because Bali's ambient is hotter (average daytime 30–32°C versus 22–25°C in Sydney), the humidity load on the unit is much higher, and most villas have 3.5–4m ceilings with single-glazed louvres, which don't insulate.
What "PK" means
PK stands for "paardenkracht" (Dutch horsepower), the legacy unit Indonesian AC sellers use. The conversion is roughly:
- 0.5 PK ≈ 5,000 BTU
- 1 PK ≈ 9,000 BTU
- 1.5 PK ≈ 12,000 BTU
- 2 PK ≈ 18,000 BTU
- 2.5 PK ≈ 24,000 BTU
If a salesperson quotes you in PK, just convert to BTU using this table.
Common sizing mistakes in Bali
Mistake 1: Trusting the builder. Bali villa builders almost always under-spec to save the client money on the unit. A 0.5 PK in a 15m² bedroom is the most common one we see — it'll never reach setpoint and will run 24/7.
Mistake 2: Going too big. This is rarer but worse — an oversized unit short-cycles, which means it cools the room fast then shuts off before it can dehumidify. The room ends up cool but clammy, and the unit wears out faster.
Mistake 3: Forgetting glass. A bedroom with a wall of west-facing glass needs 1.5 PK even at 18m². Account for sun load.
Mistake 4: Ignoring the kitchen. An open-plan living-kitchen adds about 30% to the cooling load. A 30m² open-plan space with a kitchen needs 2 PK (18,000 BTU), not 1.5 PK.
How we size on a survey
For villas we look at:
- Floor area in m²
- Ceiling height (most Bali villas are 3.5–4m, not 2.4m like a hotel)
- Glazing area and orientation (west-facing is the worst)
- Whether the kitchen is open-plan
- Whether the room shares an opening with another conditioned space
- Number of occupants at peak (each adult adds ~400 BTU)
- Heat-generating appliances (oven, plasma TV, etc.)
We then add a 15% safety margin for tropical-storm hot days when the unit needs to recover quickly. The result is the right BTU — which is then matched to the next size up in the actual product range.
Get a free sizing quote
Send us a photo of the room and the dimensions on WhatsApp. We'll come back with the right PK rating and a fixed install quote.