BTU: an education.

Earlier this month I posted an Ask Dave that mentioned BTU.  When you talk to heating contractors this little acronym always comes up but in your regular, day to day life, it simply doesn't.  So I wanted to explain what it means to help you know which system you should purchase.

BTU is short for British Thermal Unit.  Each BTU equals the amount of heat required to raise one pound of water one degree.  One pound of water is about one pint.

So you create 450 BTUs per hour in your regular, every day life.  You, every hour, create enough heat to bring more than three pints of water from room temperature to a boil.  You may not know you created BTUs but really you are a furnace.  I love to put my freezing cold feet as close to my hubbie as possible without them actually touching him (he complains big time if they get too close!)  That's because I'm taking advantage of his BTUs.

Furnaces are rated on how many BTUs they create per hour.  So a 75,000 BTUs furnace will create 75,000 BTU's in an hour.  And unlike your 450 BTUs, a furnace has a blower to ship that wonderful warmth all around your home through insulated ducts.

So how can knowing this help you buy a new heating system?

In two main ways.  First, your new furnace will be sized according to the size of your house and the insulation in your walls.  And bigger is not better, in this case.  The more BTUs your furnace pumps out at once, the sooner it will shut off.  And a furnace that cycles more often costs more money than one that pumps out heat slow & steady.  But too small and it won't keep your house warm enough.  So understanding BTUs can help you choose the furnace and contractor who understand sizing best.

Second, as in the previous Ask Dave, comparing BTU's in one type of heat, like propane vs. wood, can help you choose the most cost effective type of heat available to you.

So there ya go.  BTUs for the rest of us.

Maybe later I'll explain heat pumps and air conditioners being measured in tons and in how many BTUs they suck out of your house per hour.  Intrigued?  Coming soon to a blog in the summer!