1 watt is approximately 3 412 btu per hour.
Gas furnace btu for square footage.
Furnaces are rated on their btus of energy consumption not their btus of energy output.
Thanks to the equation we know we need 80 000 btus of heat.
We included an example for you below.
Take your home s square footage and multiply it against the btus your climate requires.
For example a furnace with an input btu can have an efficiency of 80.
2 000 square feet x 40 btus 80 000 btu output required.
That means the furnace will produce 80 000 btu of heat.
What is a btu.
Calculate how many btus you need to heat a room or even a house with a wood burning pellet or gas fireplace insert or stove.
Furnaces have come a long way in efficiency over the past few decades.
Average square and cubic footage.
It is approximately the energy needed to heat one pound of water by 1 degree fahrenheit.
The british thermal unit or btu is an energy unit.
The actual production of heat called the output btu will be the main factor in deciding which heating unit is right for your.
A high efficiency furnace generating 100 000 british thermal units btu with a 93 percent rating will produce significantly.
For this example using an 80 efficient furnace the 1900 square foot home above would require a 90 000 btu input furnace that produces 72 000 btu s of heating which is close enough to the 76 000 btu s required using the climate heating factor.
But before we buy an 80 000 btu furnace there s furnace efficiency to consider as well.
At 40 to 45 btus per square foot you d need a 100 000 to 112 500 btu.
For cooler climates a very broad estimate of furnace sizing is to select one that generates 40 to 45 btus per square foot.
A more efficient furnace will output more btus of heat than a less efficient furnace with the same btu rating.
This btu calculator will determine what hearth product size is required with only a few steps and information such as square footage sq ft.
Another variable in determining your energy needs is space both in terms of square footage and cubic footage.
1 btu 1 055 joules 252 calories 0 293 watt hour or the energy released by burning one match.
For example if a furnace is rated at 100 000 btus and is 80 efficient then the heat output will be 80 000 btus 100 000 x 8.