1. What is an Air Conditioning Size Calculator?

Definition: This calculator estimates the required air conditioning capacity in kilowatts based on room area and the unit's Energy Efficiency Ratio (EER).

Purpose: It helps homeowners and HVAC professionals determine the appropriate AC size for optimal cooling efficiency and energy savings.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Required AC capacity (kilowatts)
• \( A_{room} \) — Room area (square meters)
• \( EER \) — Energy Efficiency Ratio (dimensionless)
• 44.6 — Conversion factor (W/m² to BTU/hr)
• 3412 — Conversion factor (BTU/hr to kW)

Explanation: The formula converts room area to cooling load in BTU/hr, then converts to kW while accounting for the unit's efficiency.

3. Importance of Proper AC Sizing

Details: Correct AC sizing ensures efficient operation, prevents short cycling, maintains comfort, and reduces energy costs.

4. Using the Calculator

Tips: Enter the room area in square meters and the AC unit's EER rating (default 3.5). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is EER and where do I find it?
A: Energy Efficiency Ratio is the cooling capacity (BTU/hr) divided by power input (W). Find it on the AC unit's specification sheet or EnergyGuide label.

Q2: What's a typical EER rating?
A: Standard units range 8-12 EER, while high-efficiency models can reach 12-15 EER. The default 3.5 in the formula accounts for conversion factors.

Q3: Should I round up the calculated size?
A: Generally round up to the nearest standard unit size (0.5kW increments), but avoid significantly oversizing.

Q4: What other factors affect AC sizing?
A: Ceiling height, insulation, windows, climate, and heat-generating appliances may require adjustments to the calculation.

Q5: How does this compare to the "1 ton per 500 sq ft" rule?
A: This provides a more precise calculation accounting for efficiency, while the rule-of-thumb assumes average conditions.