Convert Volt-Ampere to BTU per Hour (VA → BTU/h)

Converting volt-amperes to BTU per hour is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in volt-amperes

   Start with the number of volt-amperes (VA) you want to convert.
2. 2
   Multiply by 3.412142

   The conversion factor from VA to BTU/h is 3.412142. Multiply your value by this number.
3. 3
   Read the result in BTU per hour

   The result is your value in BTU per hour (BTU/h).

Multiply the value in volt-amperes by 3.412142. For the reverse direction, multiply by 0.293071.

• ✓VA = V × A (RMS).
• ✓For purely resistive loads, VA = W.
• ✓For motors, computers: VA > W (power factor < 1).

• ✗Treating VA and W as identical — only true for resistive loads.
• ✗Buying UPS by W when VA rating is required.
• ✗Ignoring power factor in transformer sizing.

What is the Volt-Ampere?

The volt-ampere (VA) is the SI unit of apparent power in alternating-current (AC) electrical systems. Equal to volts times amperes, the VA represents the magnitude of power flowing in an AC circuit before accounting for the phase relationship between voltage and current. For purely resistive loads (incandescent bulbs, heaters), 1 VA = 1 W. For reactive loads (motors, transformers, fluorescent lights), the apparent power (VA) is larger than the real power (W) because of the phase shift — the ratio is the 'power factor.' Transformers, UPS units, and generators are rated in VA or kVA (kilo-VA) because they must handle the apparent power, not just the real power. A typical home UPS for a desktop computer is 600–1,500 VA. The VA relates to the watt (1 VA = 1 W only at unity power factor), the kilovolt-ampere (1 kVA = 1,000 VA), and the megavolt-ampere (1 MVA = 10⁶ VA — used in utility-scale transformers).

• Transformer sizing
• Uninterruptible power supply (UPS) ratings
• Generator capacity

What is the BTU per Hour?

BTU per hour (BTU/h or BTUh) is the standard rating for American heating, air-conditioning, and refrigeration system capacity. A window air conditioner is typically 5,000–12,000 BTU/h, central residential AC ranges 24,000–60,000 BTU/h, and commercial chillers reach 100,000–1,000,000+ BTU/h. The unit's persistence in HVAC reflects American engineering tradition: it directly links cooling/heating capacity to the BTU energy unit familiar in gas-fired equipment. 12,000 BTU/h equals 'one ton of refrigeration' (a unit derived from the heat needed to melt 1 ton of ice in 24 hours), so AC sizes are sometimes given in 'tons' (a 3-ton AC = 36,000 BTU/h). BTU/h relates to the watt (1 W ≈ 3.412 BTU/h), the kilowatt (1 kW ≈ 3,412 BTU/h), and the ton of refrigeration (12,000 BTU/h = 1 ton). Outside the US, kW is dominant for HVAC capacity.

• US air conditioners and heat pumps
• US furnace and boiler ratings
• Some industrial heat-exchanger specs