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Why Add Duct Renovation to Equipment Replacement?

Why Add Duct Renovation to Equipment Replacement?

Would you like fries with that furnace?

Once your customers make the decision to buy, their next decision is to be sure the job gets done right. Better service companies have learned to look beyond the box and offer additional services that most customers need and want. Let’s take a look at how one such service, duct renovations, can be easily added to equipment replacements.

Duct renovation refers to the process of testing, diagnosing, repairing, and balancing duct systems. Typically this service is offered to a customer at the time a contractor proposes an equipment replacement, although more contractors are including this offering with a service call when the need is apparent.

For years, the primary emphasis of the HVAC industry has been to repair or replace the equipment. While this will always be the core of your business, we’ve discovered through testing that the real solutions to comfort and efficiency are found by renovating the duct system. Equipment replacement alone cannot deliver the efficiency you are promising customers.

More than Duct Sealing

System performance depends on duct performance. Equipment performance alone is critical, but is only one piece of the puzzle. Yet, by their actions, 90% of HVAC contractors assume the duct system operates perfectly forever and fail to address it again after initial installation. If you install new equipment on an existing duct system without renovation, you’re busted!

Today’s system performance testing and rating confirms that new replacement equipment often operates at less than 60% of laboratory-rated capacity if it’s simply “hooked up” to an existing duct system. Once you help customers understand this fact, selling additional services is easier.

“Duct sealing” is a short-cut method that claims to upgrade duct systems but decreases system efficiency nearly 50% of the time due to increased static pressure.

Generally duct systems are undersized when installed in today’s tight residential conditions. Most contractors, including those who use the out-of-the-box manual D programs, generally size ducts equivalent to .10 in. on a duct-sizing calculator. When these duct systems are simply sealed, typical static pressures often exceed .90–in. Combined with the fact that most fans in these systems are rated at a maximum total external static pressure of .50-in., the result is airflow of 300 CFM per ton or less.

Add a Few Ducts

Most duct renovations include adding at least one major return duct to relieve excess static pressure. Renovations also usually include the addition of several supply ducts, some duct suspensions, replacing restrictive grilles, and a few other essential performance enhancing steps.

Filter pressure drops have climbed through the ceiling in an attempt to get higher efficiency numbers. So duct renovations often include adding two or more filters to the system to reduce filter pressure drop. Then, when the duct system is performing well and each room has required airflow, refrigerant charge and combustion efficiency can be addressed.

The real truth in the matter is that each duct system is a “living and breathing” device (although most operate like they’re suffering from asthma) so each has to be tested, diagnosed, and repaired individually. Quick fixes made by slapping on a bucket of mastic just don’t do the job.

Service Company Benefits

A significant reward is available for those willing to learn this new trade and pay the price to learn to deliver top quality systems to their customers. The business benefits of diagnosing systems and then prescribing duct renovations are rock solid.

These benefits include:

  •       Building credibility with customers by teaching them about their systems while testing.
  •       Enabling customers to make their own decisions based on real-time system performance.
  •       Increasing closing rates for salespeople and reducing the number of sales calls required to meet sales goals (Closing rates often double using test and teach selling methods).
  •       Increasing the price of each change-out by 25% to 40% by including duct renovation.
  •       Earning 60% to 80% gross margins on a portion of your work that has little or no competition. The financial formula that accompanies duct renovation discloses a two-to-ten times increase in job net profits.
  •       You can finally fulfill your efficiency promises to customers. Deliver duct efficiency that equals equipment efficiency.

Duct renovation provides a new opportunity for those who can handle the commitment, step up to the plate, and deliver the best quality systems in the industry.

Embracing change is a challenge, but it offers great rewards. Remember, there are no silver bullets or quick fixes, just the opportunity to deliver a better product and service by dismissing your competition and separating yourself from the pack of box sellers.

Yes, this is an industry inside our industry. It’s a small group, comparatively speaking. It seems there’s always room at the top.

Rob “Doc” Falke serves the industry as president of National Comfort Institute an HVAC based training company and membership organization. If you're an HVAC contractor or technician interested in a free Duct Renovation Procedure, contact Doc at [email protected] or call him at 800-633-7058. Go to NCI’s website at for free information, articles, and downloads.

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