Designing the Perfect System

The latest HVAC sizing software is easier to use and more accurate than ever. As part of an optimal system design, it will enhance your reputation as a pro.

The best 21st century HVAC contractors use software to perform ACCA Manual J-based load calculations on each job. Unfortunately, those contractors only account for about 10 percent of the industry. The remainder still cling to outdated rules-of-thumb in which system size depends solely on how big the home is—one ton of cooling capacity per 500 or 600 square feet of living area, for example. The problem is that contractors who use rule-of-thumb are shortchanging their customers and missing a chance to make more money.

That's because rules-of-thumb don't work. Most homes have unique features that affect the heating and cooling load and even two new homes with similar floor plans and square footage may be oriented in different ways, leading to variations in solar gain and higher or lower demands on the HVAC system. This can lead to cold spaces in winter, short-cycling equipment that doesn't remove enough humidity in summer, and of course higher energy bills.

And in many jurisdictions, you can no longer pull a permit or qualify the customer for a utility rebate without a Manual J report. As this trend grows, you will eventually have to switch to software-based sizing anyway. Why not get there before your competitors?

Many contractors want to switch to a more accurate sizing method, but they worry about the time required to learn it, and assume it will require extra work that adds cost to the job. So they convince themselves that the old method is good enough.

The good news is that today's sizing software is easy to use and makes simple load calculations painless. In the past the contractor had to spend hours measuring the home or taking dimensions from a set of plans, then keying the numbers into the computer. Today, however, programs like CoolCalc and WrightSoft eliminate most of this effort: they use Google maps to get the home's footprint and orientation, then access local building code and tax records to determine how it was likely built. After giving the contractor the option of editing this data, the software generates a complete written report.

Of course, sizing is only part of the comfort equation. Training programs such as the Residential System Design course offered by HVAC Learning Solutions (a division of Lennox Industries International), offer a deeper dive by covering load calculations and system sizing, as well as ductwork design and balancing.

The combination of sophisticated software and knowledgeable duct design will give you credibility with customers as a cutting-edge company that knows what it's doing. Customers will likely see you as a trusted advisor who uses impartial data to solve their problems and save them money. And being a trusted advisor puts you in a stronger position to sell additional products like air filtration, high-tech thermostats and higher efficiency equipment.

Given the multiple benefits, there's no reason not to become a 21st century HVAC contractor.

Did you know that HVAC Learning Solutions offers a course in Residential System Design?
Sharpen your system design skills and boost your profits.


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