Definition: The total amount of heat that a refrigeration system must remove to maintain desired temperature. Measured in watts (W) or kilowatts (kW).
Heat Load Components::
1. **Transmission Load**: Heat entering through insulation (walls, floor, ceiling, doors)
2. **Product Load**: Heat removed to cool product from ambient to storage temperature
3. **Infiltration Load**: Warm air entering when doors open
4. **Equipment Load**: Heat from lights, motors, people
5. **Respiration Load**: Heat generated by fresh produce (if applicable)
6. **Solar Load**: Radiant heat from sun on vehicle exterior
Why It Matters: Accurate heat load calculation is essential for proper refrigeration system sizing. Undersized systems cannot maintain temperature; oversized systems cycle inefficiently and cost more.
Gauteng Consideration: Altitude reduces cooling capacity by ~18%, so equipment must be sized accordingly (heat load ÷ 0.82 = required sea-level capacity).
Related Terms: Thermal Load Calculator, Insulation, U-Value, Altitude Derate Factor
Use Tool: Thermal Load Calculator (altitude-compensated for SA regions)