Question 1

How many BTU is 1 ton of cooling?

Accepted Answer

1 ton of refrigeration equals 12,000 BTU per hour (BTU/hr). This unit originates from the amount of heat required to melt one short ton (2,000 lb) of ice in 24 hours, which equals 288,000 BTU/day or 12,000 BTU/hr. It remains the standard unit for HVAC cooling capacity in North America.

Question 2

How do I convert BTU to kW?

Accepted Answer

To convert BTU/hr to kilowatts (kW), divide by 3,412.14: kW = BTU/hr ÷ 3,412.14. Conversely, to convert kW to BTU/hr, multiply by 3,412.14. For quick mental math: 1 ton of cooling ≈ 3.517 kW, and 1 kW ≈ 3,412 BTU/hr.

Question 3

What does MBH mean in HVAC?

Accepted Answer

MBH stands for "Thousand BTU per Hour" — the "M" is the Roman numeral for 1,000. It is commonly used in HVAC equipment specifications and engineering schedules to express large heating and cooling capacities more conveniently than writing out the full BTU/hr value. For example, a 60 MBH boiler produces 60,000 BTU/hr.

Question 4

How many tons is a typical home AC?

Accepted Answer

A typical residential central air conditioner ranges from 1.5 to 5 tons (18,000 to 60,000 BTU/hr), with most homes requiring 2 to 4 tons. The correct size depends on the home's square footage, insulation, climate zone, window area, and occupancy. A common rule of thumb is 1 ton per 400–600 sq ft, but a proper Manual J load calculation is recommended for accurate sizing.

Question 5

What is the difference between BTU and BTU/hr?

Accepted Answer

A BTU (British Thermal Unit) is a unit of energy — the amount of heat needed to raise 1 pound of water by 1°F. BTU/hr is a unit of power (rate of energy transfer). HVAC equipment is rated in BTU/hr because it continuously transfers heat at a rate, not a one-time energy quantity. When HVAC professionals say "BTU," they almost always mean BTU/hr.