Free AC Vastu and Size Calculator
AC Size Calculator (BTU / Ton)
Step 1: Room Size
- Length (ft) × Width (ft) = Area (sq.ft)
Step 2: Basic Formula
AC Tonnage = Area ÷ 120
Step 3: Adjustments
Add extra load:
- +0.1 ton per 2 people
- +0.1–0.2 ton if top floor
- +0.1 ton for heavy sunlight
- +0.2 ton for kitchen/commercial use
Quick Reference Table
| Room Size (sq.ft) | AC Size |
|---|---|
| 80–120 | 0.8 – 1 Ton |
| 120–180 | 1 – 1.5 Ton |
| 180–250 | 1.5 – 2 Ton |
| 250–350 | 2 – 2.5 Ton |
AC Vastu Calculator
Ideal AC Placement (Indoor Unit)
| Direction | Result |
|---|---|
| North / East | Best airflow & positivity |
| West | Acceptable (use curtain/insulation) |
| South-West | Avoid (energy imbalance) |
Outdoor Unit Placement
| Direction | Recommendation |
|---|---|
| North-West | Best |
| South-East | Good |
| North-East | Avoid |
Airflow Direction
- Air should flow towards North or East
- Avoid direct airflow on bed (health issue)
Example Calculation
👉 Room: 12 × 15 = 180 sq.ft
👉 Base AC Size = 180 ÷ 120 = 1.5 Ton
👉 Add:
- 3 people → +0.1 ton
- Top floor → +0.1 ton
👉 Final = 1.7 Ton → Choose 1.5 or 2 Ton AC
Frequently Asked Questions
1. What size AC do I need for my room?
The required AC size depends on your room area. A simple rule is:
- Divide room area (sq.ft) by 120
Example: 150 sq.ft room ≈ 1.2 ton AC (choose 1–1.5 ton).
2. Is 1.5 ton AC enough for a bedroom?
Yes, a 1.5 ton AC is ideal for rooms between 120–180 sq.ft.
If the room gets direct sunlight or is on the top floor, you may need slightly higher capacity.
3. Which direction is best for AC as per Vastu?
The best directions to install an AC indoor unit are North or East.
Avoid placing AC in the South-West direction as per Vastu principles.
4. Where should the AC outdoor unit be placed?
The outdoor unit should ideally be installed in the North-West or South-East direction.
Avoid placing it in the North-East direction.
5. Does ceiling height affect AC size?
Yes, if your ceiling height is more than 10 feet, you should increase AC tonnage for effective cooling.
6. How many BTU is 1 ton AC?
1 ton AC = approximately 12,000 BTU (British Thermal Units).
7. Should I choose inverter or non-inverter AC?
Inverter ACs are more energy-efficient, quieter, and provide consistent cooling.
They are recommended for long-term savings.
8. Can I install AC above my bed?
It is not recommended to install AC directly above the bed, as direct airflow can cause discomfort and health issues.
