Cooling Load Calculator by Tons of Concrete

Cooling Load for Roof, Wall or Glass Given Corrected Cooling Load Temperature Difference Calculator

Cooling Load Formula:

\[ Q = U_o \times A_r \times CLTD_c \]

Overall Heat Transfer Coefficient:

W/m²·K

Area of Roof/Wall/Glass:

m²

Corrected Cooling Load Temperature Difference:

Tolerance:

Cooling Load (W):

1. What is Cooling Load Calculator?

Definition: This calculator estimates the cooling load for roofs, walls or glass based on heat transfer coefficient, surface area, and temperature difference.

Purpose: It helps HVAC professionals and engineers determine the cooling requirements for buildings and structures.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = U_o \times A_r \times CLTD_c \]

Where:

\( Q \) — Cooling load (Watts)
\( U_o \) — Overall heat transfer coefficient (W/m²·K)
\( A_r \) — Area of roof/wall/glass (m²)
\( CLTD_c \) — Corrected cooling load temperature difference (K)

Explanation: The cooling load is calculated by multiplying the heat transfer coefficient by the surface area and the temperature difference.

3. Importance of Cooling Load Calculation

Details: Accurate cooling load estimation ensures proper HVAC system sizing, energy efficiency, and occupant comfort.

4. Using the Calculator

Tips: Enter the heat transfer coefficient (default 0.25 W/m²·K), surface area in m², temperature difference in K, and optional tolerance percentage (default ±5%).

5. Frequently Asked Questions (FAQ)

Q1: What is CLTDc?
A: Corrected Cooling Load Temperature Difference accounts for the time-varying temperature difference between outdoor and indoor air.

Q2: Typical Uo values?
A: Varies by material: Single glass ~5.0, insulated wall ~0.5, well-insulated roof ~0.3 W/m²·K.

Q3: Why include tolerance?
A: Tolerance accounts for measurement errors, material variations, and real-world conditions.

Q4: How to find CLTDc values?
A: Use ASHRAE tables or specialized software based on construction type, orientation, and location.

Q5: Can this be used for whole buildings?
A: This calculates load for one surface. For whole buildings, sum loads from all surfaces plus internal loads.