One could argue that the noise culprit is the HVAC system more so than it should be. But, with acoustical panels, plenums, and enclosures available, systems do not have to be loud. Other equipment aimed to put an end to the noise in a system includes specialty air-handling units, stack silencers, industrial fan silencers, HVAC silencers and silencing systems, "floating" floors, and vibration isolation systems. In other words, if there is noise - and it can be pinpointed to the HVAC system - it can be corrected. Or, at the very least, minimized.
The company can cite 18 com-mon silencing problems, and noted it can provide solutions for each. Among its list of no-nos are limited silencer connection sizes and insufficient straight duct. Regarding the latter, the company said duct layouts are far from ideal in real life applications. Real life systems quite often do not have the recommended spaces required for straight silencers. As a result, silencers located in close proximity (three to five duct diameters, it recommends) to fans, elbows, plenums, fittings, etc. "will result in an increase in silence pressure drop and airflow-generated noise due to aerodynamic system effects." (For a complete look at the company's "18 Common Silencer Problems and Their Solutions," go to www.vibro-acoustics.com.)