When using multiple 90-degree elbows in an electric dryer duct, how much length should be deducted for each additional elbow?

In the context of duct installation, particularly for an electric dryer, it is important to consider airflow and potential restrictions caused by bends and turns in the duct. When installing ducts, each 90-degree elbow creates turbulence and reduces the effective length of the duct. This is because elbows restrict airflow, which can lead to diminished performance and potential overheating if not accounted for properly.

For each additional 90-degree elbow, a deduction of 2 feet is recommended. This value is established based on industry standards, which take into account the increase in resistance due to the bend in the duct. Therefore, by deducting 2 feet for each elbow, you maintain a more accurate account of the actual effective length of the duct, allowing for better airflow calculations and ensuring optimal dryer performance.

If the deduction were too low, it would lead to a longer effective ducting length than necessary, possibly resulting in dryer inefficiency or increased drying times. In contrast, excessive deductions could indicate insufficient duct length, leading to other performance issues. Thus, the choice to deduct 2 feet aligns with the need for effective and efficient ventilation in dryer installations.