The Significance of the BTU

To put that in perspective, an average size candle will put out roughly 76 BTU per minute.

In the United Kingdom, there are hundreds of festivals every year that celebrate the mornings before the internal combustion engine. This was when steam power drove the industrial revolution. “Steam rallies” are often held at restored train stations or even at water and wastewater pumping stations where large triple-expansion steam engines power the pumps that once moved the water. In those mornings, precise measurements of steam power did not exist, and we all guess what happens when too much pressure is applied inside a closed system. Heating, Ventilation & A/C had not yet been invented but steam radiators were commonplace to heat buildings and homes. When determining the size of a radiator, pipefitters used crude and imprecise calculations based on the room’s cubic feet and then adding a particular “fudge factor” as a safety measure. History is still “fuzzy” on the origin of the British Thermal Unit or BTU, but it led the way for early engineers to make wonderful strides in heating. It also led to the invention of a/c in the early 20th century, a BTU is simply defined as “the amount of heat required to raise the temperature of a single pound of water by a single-degree Fahrenheit”. To put that in perspective, an average size candle will put out roughly 76 BTU per minute. Steam radiators are inefficient because it takes a lot of energy to create steam from warm water. With Heating, Ventilation & A/C it is much more crucial to have a correctly sized unit. A component that is too large and transfers too many BTU’s is care about using a sledgehammer to kill a fly. An Heating, Ventilation & A/C that is too small will not be able to keep up with the demands of cooling and heating a giant room.

Heating maintenance