Home Heating and Cooling Loads Explained
Heating and cooling loads determine how much heat or air conditioning is needed in a building. Contractors must accurately calculate load to determine what size HVAC system to install. A system’s capacity is the amount of heating or cooling it can provide. To achieve optimum efficiency in your home, the load and capacity must align.
Design Loads: Averages for Ideal Conditions
A building’s design load is calculated using design temperatures. These aren’t the actual temperatures in or outside your home, but averages. Indoor design temperatures are the recommended temperatures a homeowner will try to maintain inside the home. It is the amount of cooling or heating needed for that particular home based on factors such as its size, and the number of occupants.
Outdoor design temperatures are more complex. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), maintains a list of summer and winter design temperatures for various locations. The winter design temperature is calculated using 30-year averages. It’s the temperature that the location stays above for 99 percent of the year, meaning that the temperature will dip below this point for only one percent of the year. The summer design temperature is what the climate stays below for 99 percent of the year.
Extreme Load: Handling Conditions
The extreme load is what your home would need to combat record highs and lows. While extreme loads can give you some interesting insight, they are not an accurate calculation for HVAC installation. If your home is properly sealed and insulated, extreme temperatures will not be a factor. There will be no need to consider the equipment’s ability to meet these extremes, which occur on average only one percent of the time.
Part Load: Most Common Temperatures
Since the design load represents a fairly extreme temperature, it does not represent what you usually experience. For the majority of the day, you will stay above or below design loads. Part loads are the more accurate representation of what you will actually experience.
For more information about heating and cooling loads, contact Sun Kook Air Conditioning, Inc. at (352) 282-4763. We provide systems and services to meet your home comfort needs. Call today to schedule an appointment!