In Part 2 of Furnaces Explained, I'm going to talk about AFUE and BTUs. Though these two words might contort your face into the 'huh' look but these two words are important for every homeowner to know (and can help save $$$).
WHAT IS AFUE?
AFUE stands for Annual Fuel Utilization Efficiency.
This measures how efficiently your furnace can utilize it's fuel.
It is a ratio of useful energy output to energy input that is expressed in %.
For example, a 80% AFUE for a gas furnace means it outputs 80 BTUs* of useful heating for every 100 BTUs of natural gas input (where the rest may be wasted heat in the exhaust).
*BTUs will be explained next, don't worry.
The more efficient your furnace, the more heat you will get per unit of fuel.
Believe the self pronounced "HVAC Expert" when I say, AFUE Matters!
SIZE & EFFICIENCY, WHY IT MATTERS
(The BTUs thing)
BTU is a unit of measurement for energy. One BTU is equal to the amount of energy used to raise the temperature of one pound of water one degree Fahrenheit.
A gas furnace has an input rating that is expressed in BTU per hour (which represents the size of the unit).
Common sizes are 40000, 60000, 80000, 100000, and 120000 btu/hr.
It is extremely important that your unit is the proper size for your home.
The size you choose not only influences the initial cost but everything from maintenance and monthly fuel costs to the comfort level and temperature in your home. In this situation, bigger isn't always better.
Click Here to use the BTU Calculator
Click Here to use the BTU Calculator
