What the Libra zodiac sign is all about: Libra is the seventh of the 12 zodiac signs, which begins its cycle in early fall every year during Libra seasonâwhich falls around September 23-October 22.
How it works. This schematic shows the component parts of a typical leak-down tester. The gauge on the right is held at a standard pressure by adjusting the pressure regulator while the gauge on the left shows an example reading of 85-or 15% leakage.
Duct BlasterÂ® A Duct Blaster is used to directly pressure test the duct system for air leaks, much the same way a plumber pressure tests water pipes for leaks. The Duct Blaster fan is first connected to the duct system at the air handler cabinet, or a return grille. After temporarily sealing all remaining registers and grills, the Duct Blaster fan is turned on to force air through all. Two different types of performance testing systems are used to measure duct leakage; a Duct BlasterÂ® and a Blower Door. holes and cracks in the ductwork. The fan speed is increased until a standard test pressure is achieved in the duct system.