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AC Tonnage Formula:
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The AC tonnage calculation determines the appropriate air conditioner size needed for a room based on its area. Proper sizing ensures efficient cooling, energy savings, and optimal performance.
The calculator uses the AC tonnage formula:
Where:
Explanation: The formula calculates the required cooling capacity by multiplying the room area by 25 BTU per square foot, then converts the result from BTU to tons (1 ton = 12,000 BTU).
Details: Correct AC sizing is crucial for energy efficiency, comfort, and system longevity. An undersized unit will struggle to cool the space, while an oversized unit will short-cycle, leading to humidity issues and higher energy costs.
Tips: Enter the room area in square feet. The calculator will determine the recommended AC tonnage. For irregularly shaped rooms, calculate the total area by breaking it down into regular shapes.
Q1: Why is 25 BTU per square foot used?
A: This is a standard factor for average rooms with normal ceiling height, insulation, and window exposure. Adjustments may be needed for specific conditions.
Q2: What if my room has high ceilings or many windows?
A: For rooms with high ceilings, large windows, or poor insulation, you may need to increase the BTU factor to 30-35 per square foot.
Q3: Can I use this for entire house calculations?
A: For whole-house calculations, you should calculate each room separately and sum the results, or consult an HVAC professional for a manual J calculation.
Q4: What are common AC tonnage sizes?
A: Common residential AC units come in 1.5, 2, 2.5, 3, 3.5, 4, and 5-ton capacities. Round up to the nearest available size.
Q5: Does room orientation affect AC sizing?
A: Yes, south-facing rooms with more sun exposure may require additional cooling capacity compared to north-facing rooms.