1. What is an Air Con Sizing Calculator?

Definition: This calculator estimates the required cooling power (in kW) for an air conditioning unit based on room area and energy efficiency ratio.

Purpose: It helps homeowners and HVAC professionals properly size air conditioning units for optimal performance and energy efficiency.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Required cooling power (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 Air Con Sizing

Details: Correct sizing ensures energy efficiency, proper humidity control, and prevents short cycling which can reduce equipment lifespan.

4. Using the Calculator

Tips: Enter the room area in square meters and the EER (default 3.5 for standard units). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical EER value?
A: Standard units range from 3.0-3.5, while high-efficiency units can be 4.0-5.0 or higher.

Q2: How do I find my AC unit's EER?
A: Check the manufacturer's specifications or energy guide label on the unit.

Q3: Should I round up the calculated power?
A: Generally yes, to the nearest standard unit size (0.5 kW increments).

Q4: Does this account for room insulation?
A: The basic calculation assumes average insulation. For poor insulation, add 10-20% to the result.

Q5: What about rooms with high heat loads?
A: For rooms with many windows, high ceilings, or heat-producing equipment, increase the calculated power by 15-25%.