Duct System

Efficient Ductwork is Important for Health and Energy Efficiency

Leaky ductwork can reduce the efficiency of your heating and cooling system by 20 – 60%. Friction is another issue that decreases the efficiency of your system. You want your system to be designed optimally and installed properly.

Heat Loss

Air is lost in your HVAC system through holes, leaks and poorly connected ducts. Air is usually heated or cooled far beyond the ultimate temperature. Then it mixes with the room temperature in the appropriate proportion to arrive at the target temperature. If the ductwork is leaky, you will both lose the conditioned air as it leaves through the leaks, and unconditioned air will be introduced into the system. In order to maintain the best efficiency, the lowest energy bills and the highest indoor air quality you want to insure that all ducts are properly sealed, connected and insulated.

Air Resistance in Ducts

The other significant source of system energy loss is friction in the ducts. The efficiency of an air system is generally measured by its resistance to air flow, which is called head loss. Head loss happens because of drag against the walls of the pipe, and from moving through and around valves and turns in the ducts. We can reduce these losses in several ways:

  • Make sure the insides of ducts are smooth
  • Reduce the length of the duct run
  • Reduce the speed at which the air flows through the duct
  • Increase the duct size (hydraulic radius) – this method turns out to be the most effective because doubling the diameter of the duct can cut losses by 32 times
  • Create layouts with fewer bends
  • Create layouts with a larger radii in the bends
  • Create layouts with fewer valves, fittings, or other interruptions

Have your ductwork inspected to maintain the best scenario related to your health, safety and energy consumption.