1. What is a Commercial HVAC Tonnage Calculator?

Definition: This calculator converts cooling capacity in BTU/hr to refrigeration tons, the standard unit for commercial HVAC systems.

Purpose: It helps HVAC professionals and engineers determine the appropriate system size for commercial cooling applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( T \) — Tonnage (tons of refrigeration)
• \( BTU \) — Cooling capacity (British Thermal Units per hour)

Explanation: One ton of refrigeration equals 12,000 BTU/hr, which originates from the heat absorbed by melting one ton of ice in 24 hours.

3. Importance of Tonnage Calculation

Details: Proper tonnage calculation ensures efficient system operation, prevents undersizing (inadequate cooling) or oversizing (short cycling and inefficiency).

4. Using the Calculator

Tips: Enter the total cooling capacity in BTU/hr. The value must be > 0. For whole-building calculations, first determine the total heat load.

5. Frequently Asked Questions (FAQ)

Q1: Why 12,000 BTU/hr equals 1 ton?
A: This comes from the heat required to melt one ton (2000 lbs) of ice in 24 hours (288,000 BTU/24hr = 12,000 BTU/hr).

Q2: What's typical for commercial buildings?
A: Office spaces typically need 1 ton per 400-500 sq ft, but this varies based on insulation, windows, and occupancy.

Q3: Should I round up the calculated tonnage?
A: HVAC systems come in standard sizes. Round to nearest half or whole ton, but consult an HVAC professional for final sizing.

Q4: How do I find my building's total BTU requirement?
A: Use Manual J calculations (for US) or equivalent methods considering square footage, insulation, windows, occupancy, and equipment.

Q5: Does this apply to residential systems?
A: The calculation is the same, but residential systems typically range 1-5 tons while commercial systems can be much larger.