HVAC Cooling/Heating Load Designer — Ebora Engineering Utilities 2

❄️ Cooling / Heating Load

HVAC Cooling/Heating Load Designer

Estimate a space's cooling (or heating) load by a simplified component method — envelope & glass conduction, solar gain, lighting, equipment, people, and ventilation — then size the supply airflow. Outputs the sensible, latent & total load in kW and tons of refrigeration, with the sensible-heat ratio.

⭐ Free to use · Balance … EP

① Mode, space & design temperatures

Indoor design DB Tᵢ (°C)

Outdoor design DB Tₒ (°C)

ΔT = |Tₒ − Tᵢ| drives all conduction terms.

Ventilation / fresh air (L/s)

Outdoor-air supply. Sensible 1.23·V·ΔT (+ latent in cooling).

② Envelope & glass conduction

Wall + roof area (m²)

Wall/roof U-value (W/m²·K)

Wall/roof CLTD (°C) — cooling only

Cooling-load temperature difference (ASHRAE). Heating uses ΔT.

Glass area (m²)

Glass U-value (W/m²·K)

③ Solar, internal & latent gains (cooling)

Solar heat-gain factor SHGF (W/m²)

Shading coefficient SC

Cooling-load factor CLF

Glass solar = A·SC·SHGF·CLF.

Lighting (W)

Equipment / appliances (W)

Occupants (persons)

Sensible heat / person (W)

Latent heat / person (W)

Humidity-ratio diff Δw (g/kg)

Outdoor − indoor humidity ratio. Vent latent = 3.0·V·Δw.

Supply ΔT (°C)

Room − supply-air temperature, default 10 °C.

③ Heating mode

In heating mode the load is the sensible heat loss through the envelope and glass plus the ventilation air, all at the winter ΔT = |Tₒ − Tᵢ|. Solar gain and internal (lighting / equipment / people) gains are ignored — they would only reduce the heating requirement, so omitting them is conservative.

❄️ HVAC load & airflow

—

Sensible + latent load · supply airflow

Component breakdown

Load totals

Sensible load

—

Latent load

—

Total load

—

Tons of refrigeration

—

Sensible-heat ratio

—

Supply airflow

—

Worked solution

⚠️ Verify the design data. CLTD, CLF, SHGF, U-values and per-person heat gains here are typical ASHRAE-style design figures. A real load calc must use the correct CLTD/CLF for the orientation, latitude, month and hour, the actual construction U-values, and proper psychrometrics for the latent load. This tool is a study/estimating aid — confirm against ASHRAE data and your course method.