Load Calculation: Fitting your HVAC to your Home
When installing a new hvac unit, you want it to be compatible with your home. To reach that ultimate comfort level for you and your unit, you have to measure load calculation, which is the thermal and cooling gain and/or loss of your home.
What exactly is load calculation?
Load calculation consists of the different factors of your home that determine how much heat or cool air a house needs. The measurements involved:
- Size of house (square footage)
- Orientation of house (i.e. does it face the sun?)
- Climate of house location
- Insulation durability
- Window size and type (single or double pane)
The combination of these measurements will accurately reflect you home's ability to contain air. Simply calculating square footage is not enough to determine how well the house holds the air. Certified contractors must also inspect insulation, window size and type (single or double pane), ductwork, and check for air leaks. These factors will determine the unit size best suited for the home.
All too often are large hvac units purchased with the belief that they operate more efficiently. As it turns out, if a unit is too big for a house, it is a waste of energy. The oversized unit will turn on and off more frequently (short cycling), and ultimately cost more money to install and maintain.
Energy Star has initiated a new program to prevent the loss of energy with oversized units, requiring that a unit cannot be more than 15% oversized.