HVAC Engineering & Thermal Management

Cooling Load

The Capacity Metric. Convert required cooling capacity between Imperial BTU/hr, Japanese/US Tonnage (TR), and International Metric Kilowatts (kW).

Tonnage (TR)
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Power (kW)
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Imperial (BTU/hr)
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Quick Sizing Rules

Avg. Home (1000 ft²)~2.0 Tons
High Sun (1000 ft²)~2.5 Tons
1.0 Ton3.517 kW

Thermal Reciprocals

The cooling load is often expressed in **BTU/hr** to match building envelope heat gain calculations. Use this tool to translate those loads into actual equipment ratings found on condenser labels.

The Physical Foundation of Climate Engineering

In the HVAC (Heating, Ventilation, and Air Conditioning) industry, "Cooling Load" is the amount of heat energy that must be removed from a space to maintain a specific temperature and humidity level. This load is the sum of **Sensible Heat** (temperature change) and **Latent Heat** (moisture removal). Converting these requirement metrics accurately is the first step in Manual J calculations and professional system commissioning.

Defining the 12,000 BTU Standard

In North America, one **"Ton" of refrigeration** is defined as exactly 12,000 BTU per hour. This legacy unit dates back to the era when ice was used for cooling; it represents the amount of cooling power generated by melting one short ton of ice in a 24-hour period. While most of the world has transitioned to **Kilowatts (kW)** for equipment rating, the US market still relies heavily on this tonnage unit for residential and light commercial equipment naming.

Capacity vs. Efficiency

It is important to distinguish between capacity (BTU/hr) and efficiency (SEER or EER). While this converter tells you the total **Work Output** required to cool a room, it does not reflect the electrical power consumed by the unit. Modern high-efficiency systems might deliver 36,000 BTU (3 Tons) of cooling while drawing significantly less electrical wattage than an older model of the same capacity.

Professional Cooling Capacity Reference

System Size BTU/hr Rating Kilowatts (kW) Typical Home Coverage
1.5 Tons 18,000 5.27 600 - 900 ft²
2.5 Tons 30,000 8.79 1200 - 1500 ft²
3.5 Tons 42,000 12.31 1800 - 2100 ft²
5.0 Tons 60,000 17.58 2500 - 3000 ft²

Related Efficiency Tools

Frequently Asked Questions

What is a Ton of Refrigeration?

A Ton of Refrigeration (TR) is the cooling power required to melt 2,000 lbs (one short ton) of ice in 24 hours. It is equivalent to 12,000 BTU/hr.

How many BTU is 1 kW of cooling?

1 Kilowatt (kW) of cooling capacity is approximately equal to 3,412.14 BTU per hour.

Why is cooling load calculation important?

Proper sizing prevents short-cycling (oversized) or insufficient dehumidification and temperature control (undersized), ensuring energy efficiency and equipment longevity.