Learn What a Load Calculation Encompasses and Why It’s Important

Load Calculation scaled

If you’re a homeowner who is looking to invest in a new HVAC system, you want to make sure the unit you’re purchasing is the right one to accommodate your household. This starts with determining the right size system that will provide heating or cooling when needed, but also not break your bottom line for installation and usage. One way in which homeowners and their technicians can figure out the right unit is by adjusting for what’s called a load calculation.

What is a load calculation?


Before splurging on a system, an HVAC contractor should help a homeowner learn what a load calculation encompasses and why it’s important. Load calculation is a formula by which contractors determine the right size system based on the square footage of your home, heating and cooling needs, and also other underlying factors. What was once a lengthy drawn-out formula to figure out a particular value, is now carried out by sophisticated computer software that essentially creates a digital model of your home, and computes the result.

An HVAC technician will have to draw a detailed plan of your house, taking down detailed information to make sure that their formulas work to your advantage as a homeowner. This can include the number of windows in a home, as well as the number of occupants or even the construction components of the house. Formulas may vary by the HVAC contractor with one simple example being taking the square footage of the home and multiplying that by the average ceiling height of the home. That number is then multiplied by the difference in desired temperature indoors and the outdoor temperature.

Determining Equipment Size


HVAC contractors understand that homeowners may not be used to this new technology in their homes, and that’s why they emphasize getting the necessary data points to determine load calculation. Most HVAC equipment operates at a single capacity and cannot alter its output. Even in some of the best places, an HVAC system may not be able to entirely adapt to varying conditions. However, this has been a hindrance in the past for technicians on a particular order because of the flux of temperatures. This could end up making for too large of a unit that expends far too much energy than needed for a home.

It is now possible to buy equipment that can alter the output in accordance with the demands brought on by various elements in and outside of the house. Ductless mini-split HVAC systems are capable of operating in a wide range of capacities. Standard split-system central units are mostly available with a single staging area, but most manufacturers offer dual-stage models that operate as needed. This type of equipment will do a better job of providing comfort and reducing monthly energy bills.

Other Factors


As mentioned, there are more factors beyond square footage that will give HVAC contractors the insight they need to draw up the blueprint for the right heating and cooling systems. Other appliances that generate heat, such as ovens and washing machines, are used by analysts to judge home heating needs. The type of roofing and overall insulation of a house from the foundation up is used to make manipulations to the load calculation, which are then used to make sure the correct formulas are being utilized.

A proper blueprint by an HVAC contractor will address the heating and cooling needs of each room to lock in the specific values which makes sure these complex formulas are delivering the right information. With these technological advances, homeowners can avoid having too small of a furnace when winter rolls around, or too large of an HVAC system that wastes energy. Make sure you’re working with an HVAC installation company that understands the importance of load calculation.

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