Air-Conditioning Load Estimator

Estimate sensible and latent cooling/heating loads for your space.

Length (ft)

Width (ft)

Height (ft)

Outdoor Dry Bulb Temp (°F)

Outdoor Relative Humidity (%)

Indoor Dry Bulb Temp (°F)

Indoor Relative Humidity (%)

Wall U-factor (Btu/hr·ft²·°F)

Roof U-factor (Btu/hr·ft²·°F)

Floor U-factor (Btu/hr·ft²·°F)

Total Window Area (ft²)

Window U-factor (Btu/hr·ft²·°F)

Window SHGC

Total Door Area (ft²)

Door U-factor (Btu/hr·ft²·°F)

Number of Occupants

Equipment Heat Gain (BTU/hr)

Lighting Heat Gain (BTU/hr)

Infiltration (ACH)

Solar Radiation Factor (Btu/hr·ft²)

Sensible Heat Gains:
- Conduction through walls, roof, floor, windows, and doors (Q=U×A×ΔT).
- Solar heat gain through windows (Q=Awindow×SHGC×Solar Radiation Factor). A default solar radiation factor will be provided, but adjustable.
- Heat gain from occupants (standard ASHRAE sensible heat per person).
- Heat gain from equipment and lighting (user-defined).
- Sensible heat gain from infiltration (Q=1.08×CFM×ΔT).
Latent Heat Gains:
- Latent heat gain from occupants (standard ASHRAE latent heat per person).
- Latent heat gain from infiltration (Q=0.68×CFM×ΔW). Humidity ratio difference (ΔW) will be estimated using simplified psychrometric formulas based on input temperatures and relative humidities.
Total Cooling Load: Sum of all sensible and latent gains.
Sensible Heat Ratio (SHR): Ratio of total sensible load to total cooling load.
Capacity Conversion: Convert total load to Tons of Refrigeration and Kilowatts.