What is the impact of duct design and pressure losses on system energy usage, and how can you minimize them?

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Multiple Choice

What is the impact of duct design and pressure losses on system energy usage, and how can you minimize them?

When ductwork has friction and fittings that create pressure losses, the fan must generate extra pressure to push the same amount of air through the system. The power the system uses is tied to the pressure rise the fan provides times the airflow, adjusted for the fan’s efficiency. So, higher losses mean the fan has to work harder, increasing energy consumption and operating costs. To keep energy use down, focus on duct design that minimizes those losses: size the ducts properly to keep air velocities in an efficient range, use smoother transitions and gradual bends to cut minor losses, seal all joints and leaks so air doesn’t escape or cause the fan to push more air than intended, and minimize the number and sharpness of bends by using larger-radius turns. Also, smoother interior surfaces reduce friction losses. Insulation matters for reducing heat transfer and the total building energy needed to maintain temperature, but the direct impact on fan energy in this context comes from reducing duct pressure losses through good design and sealing.

When ductwork has friction and fittings that create pressure losses, the fan must generate extra pressure to push the same amount of air through the system. The power the system uses is tied to the pressure rise the fan provides times the airflow, adjusted for the fan’s efficiency. So, higher losses mean the fan has to work harder, increasing energy consumption and operating costs.

To keep energy use down, focus on duct design that minimizes those losses: size the ducts properly to keep air velocities in an efficient range, use smoother transitions and gradual bends to cut minor losses, seal all joints and leaks so air doesn’t escape or cause the fan to push more air than intended, and minimize the number and sharpness of bends by using larger-radius turns. Also, smoother interior surfaces reduce friction losses.

Insulation matters for reducing heat transfer and the total building energy needed to maintain temperature, but the direct impact on fan energy in this context comes from reducing duct pressure losses through good design and sealing.

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