How do I transition from rectangular duct to the round inlet of a VAV?

Use a factory-built or shop-fabricated square-to-round transition fitting . Ensure the angle of the transition slope does not exceed 30^\circ (per SMACNA guidelines) to prevent excessive static pressure drops and turbulent air noise right before it hits the box sensor.

['Use a factory-built or shop-fabricated square-to-round transition fitting . Ensure the angle of the transition slope does not exceed 30^\\circ (per SMACNA guidelines) to prevent excessive static pressure drops and turbulent air noise right before it hits the box sensor.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Steps

• Use a factory-built or shop-fabricated square-to-round transition fitting. Ensure the angle of the transition slope does not exceed 30^\circ (per SMACNA guidelines) to prevent...

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