HVAC Calculator

Calculate heating and cooling loads, duct sizing, and equipment requirements

HVAC Load Analysis

Calculation Type

Enter HVAC specifications to calculate requirements

Residential: 400-600 BTU/sq ft
Cooling load per square foot

Commercial: 300-800 BTU/sq ft
Varies by building type

Occupants: 400 BTU/person
Heat gain from people

Round Duct: 0.785 × diameter²
Cross-sectional area formula

Air Velocity: 700-900 FPM
Recommended for residential

CFM per Ton: 400 CFM
Standard air flow rate

1 Ton: 12,000 BTU/hr
Standard cooling capacity

Oversizing: 10-20% maximum
Prevents short cycling

SEER Rating: 14+ recommended
Energy efficiency standard