Cooling & Heating Load Calculator

Estimate the thermal equipment capacity required to condition an indoor space. Calculate sensible temperature shifts, latent ambient moisture adjustments, and building envelope insulation conduction variables concurrently.

Ambient Environment Parameters

CFM (ft³/min)
°F
°F
%
%
people
sq ft (ft²)
BTU/(h·ft²·°F)

Total Estimated Cooling Equipment Capacity Required

33333 BTU/h

= 2.78 Tons of AC

Sensible Airflow Load

32533 BTU/h

Latent Moisture Load

800 BTU/h

HVAC Psychrometric Airflow Verification Trace

Sensible Airflow Load (q_s) = Air Constant × Volumetric Flow × ΔT
Envelope Conduction (q_e) = Insulation Factor × Area × ΔT
• Airflow Sensible: 1.08 × 1200 CFM × 23°F = 29808 BTU/h
• Building Envelope: 0.05 U × 1500 sq ft × 23°F = 1725 BTU/h
Total Sensible (q_s + q_e + Occupants) = 32533 BTU/h

How Building Thermal Loads Are Evaluated

In environmental engineering and building management science, sizing a heating, ventilation, and air conditioning (HVAC) system accurately requires splitting the total energy load into two distinct physical components: Sensible Heat and Latent Heat.

1. Sensible Heat Loads

Sensible heat refers to thermal energy transfers that result in a direct change in room air temperature without changing moisture levels. This energy flows into a room via solar radiation through windows, conduction through insulated walls (building envelope), operational lighting/appliances, and the body heat of human occupants.

2. Latent Heat Loads

Latent heat represents the energy required to remove or add moisture to the indoor air to maintain a comfortable humidity level. This load is heavily influenced by outdoor fresh air ventilation requirements, air infiltration gaps, and moisture released by occupants through respiration and perspiration.

By solving both fields alongside conduction coefficients simultaneously, engineers can convert the aggregate heat extraction demand into a precise refrigeration standard unit profile known as Tons of AC (where 1 Ton equals 12,000 BTU/h of heat extraction capacity).