HVAC Converter: Tons to BTU, kW, HP Calculator

Convert HVAC units instantly: tons to BTU/hr, kW to BTU, horsepower to kW, CFM calculations. Professional HVAC conversion calculator for engineers, technicians, and contractors.

HVAC Unit Converter

Standard cooling capacity conversion

Refrigeration TonsBTU per Hour
tons

HVAC Quick Reference

Common Conversions

1 ton cooling12,000 BTU/hr
1 HP0.746 kW
1 kW3,412 BTU/hr
1 CFM0.472 L/s

Typical Design Values

Residential cooling: 1 ton per 400-600 sq ft
Office buildings: 1 ton per 300-400 sq ft
Good SEER rating: 16+ SEER
Ductwork velocity: 600-900 FPM

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HVAC Conversion Reference Table

From UnitTo UnitMultiply ByApplication
1 Ton12,000 BTU/hr12,000Cooling capacity
1 HP0.746 kW0.746Motor power
1 kW3,412 BTU/hr3,412Electric heating
1 CFM0.472 L/s0.472Airflow rate
1 Ton3.517 kW3.517Cooling load
1 MBH0.293 kW0.293Heating load

AC Tonnage to BTU Chart (Tons to BTU/hr and kW)

1 ton of air conditioning equals 12,000 BTU/hr, which is 3.517 kW. To convert AC tonnage to BTU, multiply the tons by 12,000; to convert refrigeration tons to kW, multiply by 3.517. So a 2-ton AC is 24,000 BTU/hr, a 3-ton is 36,000 BTU/hr, and a 5-ton is 60,000 BTU/hr. Use the chart below for every common residential AC size.

AC Size (Tons)BTU/hrkW (Cooling)Approx. Area Cooled*
1 ton12,0003.52 kW~600 sq ft
1.5 ton18,0005.28 kW~900 sq ft
2 ton24,0007.03 kW~1,200 sq ft
2.5 ton30,0008.79 kW~1,500 sq ft
3 ton36,00010.55 kW~1,800 sq ft
3.5 ton42,00012.30 kW~2,100 sq ft
4 ton48,00014.07 kW~2,400 sq ft
5 ton60,00017.58 kW~3,000 sq ft

*Area cooled is a rough guide at about 600 sq ft per ton and varies with climate, insulation, ceiling height, and sun exposure. For a precise figure, run a Manual J load calculation. Need a single conversion? Use our dedicated Tons to BTU and BTU to kW calculators.

How to Convert HVAC Units

Cooling Load Conversions

Tons to BTU/hr: multiply by 12,000

BTU/hr to tons: divide by 12,000

Example: 3 tons × 12,000 = 36,000 BTU/hr

Power Conversions

HP to kW: multiply by 0.746

kW to HP: divide by 0.746

Example: 10 HP × 0.746 = 7.46 kW

Heat Load Conversions

kW to BTU/hr: multiply by 3,412

BTU/hr to kW: divide by 3,412

Example: 5 kW × 3,412 = 17,060 BTU/hr

Airflow Conversions

CFM to L/s: multiply by 0.472

L/s to CFM: divide by 0.472

Example: 1000 CFM × 0.472 = 472 L/s

HVAC Design Guidelines

Cooling Load Rules of Thumb

Residential homes1 ton / 400-600 sq ft
Office buildings1 ton / 300-400 sq ft
Retail spaces1 ton / 250-350 sq ft
Restaurants1 ton / 150-250 sq ft

System Performance Standards

High efficiency AC: SEER 16+ (≤0.75 kW/ton)
Duct velocity: 600-900 FPM max
Return air CFM: 400 CFM per ton
Heat pump COP: 3.0+ at 47°F

HVAC Conversion FAQ

How many BTU/hr is 1 ton of cooling?

1 ton of cooling equals 12,000 BTU/hr. This is the standard refrigeration ton used in HVAC calculations. To convert tons to BTU/hr, multiply by 12,000.

How do you convert horsepower to kilowatts?

To convert horsepower to kilowatts, multiply by 0.746. For example: 10 HP × 0.746 = 7.46 kW. This conversion is used for motor sizing and electrical load calculations.

What is the CFM per ton rule?

The standard rule is 400 CFM per ton of cooling. This means a 3-ton AC unit should move 1,200 CFM. Proper airflow is critical for system efficiency and comfort.

How many square feet does 1 ton of AC cool?

Generally, 1 ton of cooling covers 400-600 sq ft in residential applications, but this varies based on insulation, ceiling height, windows, and climate. Commercial spaces typically require more cooling.

What is a good SEER rating for air conditioners?

A SEER rating of 16 or higher is considered high efficiency. The minimum standard is 14 SEER. Higher SEER ratings mean lower energy consumption and operating costs.

How many BTU is a 1.5 ton AC?

A 1.5 ton AC unit produces 18,000 BTU/hr (1.5 × 12,000). In metric terms that is about 5.28 kW of cooling capacity.

Is 24,000 BTU a 2 ton AC?

Yes. 24,000 BTU/hr equals exactly 2 tons of cooling, because 1 ton = 12,000 BTU/hr. Divide any BTU/hr rating by 12,000 to get the tonnage.

What is 3 ton in BTU?

3 tons of cooling equals 36,000 BTU/hr (3 × 12,000), or about 10.55 kW. This is a common size for cooling roughly 1,800 sq ft of residential space.

How do you convert refrigeration tons to kW?

Multiply refrigeration tons by 3.517 to get kilowatts of cooling. For example, a 1 ton unit is 3.517 kW, a 2 ton unit is 7.03 kW, and a 5 ton unit is 17.58 kW. To go the other way, divide kW by 3.517.

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