HVAC Load (TR) to Electrical Load (kW) Conversion

In HVAC projects, cooling load is calculated in TR (Ton of Refrigeration), but electrical systems are designed in kW.

Understanding this conversion is essential for equipment sizing and power planning.

What is 1 TR?

→1 TR = 3.517 kW (Cooling Capacity)

→Represents heat removal rate

HVAC to Electrical Conversion

→Cooling load Electrical power directly

→Because actual power depends on system efficiency (COP / EER)

Basic Conversion

→Cooling Load (kW) = TR x 3.517

Example:

→10 TR = 35.17 kW (Cooling capacity)

Electrical Power Input

→Electrical kW = Cooling kW COP

Typical values:

→COP = 3 to 5 (depends on system)

Example:

→35.173.5 ≈ 10 kW electrical load

Practical Thumb Rule

→1 TR≈ 0.8 to 1.2 kW (electrical)

(depends on system efficiency)

Why It Matters

→Electrical panel sizing

→DG/transformer sizing

→Cable & breaker selection

→Energy consumption estimation

Comments

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