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Apprentice Q&A · #176

How do I ensure all VAV damper blades are in the open position before system blow-down?

4th YearTAB / Startup PrepRED · Stop / Verify

Coordinate with the temperature controls technician to command all digital VAV box actuator motors to drive into their 100% full open position overrides via their central software control board. * If the controls aren't powered on yet, you must manually decouple the actuator shaft set-screws and rotate the damper blades by hand to full open before starting the primary fans.

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Plain-English answer

Coordinate with the temperature controls technician to command all digital VAV box actuator motors to drive into their 100% full open position overrides via their central software control board. * If the controls aren't powered on yet, you must manually decouple the actuator shaft set-screws and rotate the damper blades by hand to full open before starting the primary fans.

Field checklist

Ask Foreman

Hey boss, I’m on tab / startup prep and need verification before I touch this: How do I ensure all VAV damper blades are in the open position before system blow-down? Do you want me to stop here and check the approved detail, submittal, or inspector/manufacturer requirement first?

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Verify before acting

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.

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