Drains shall be provided at _______ points in horizontal ducts.

Drains shall be provided at _______ points in horizontal ducts.

• A. High
• B. Low
• C. Accessible
• D. Transition

Answer: (B)

In horizontal ducts, condensate forms when air is cooled and moisture condenses on the duct surface. Placing drains at the lowest points lets that condensate flow away by gravity to the drain, preventing pooling and leaks. High points would simply collect water, leading to drips, corrosion, or mold. Accessibility matters for maintenance, but the fundamental requirement is drainage from the lowest point, so a drain at a low point is the correct practice. Drains at transition points aren’t about enabling gravity drainage, and while you want access for service, it doesn’t override the need to place the drain at the lowest point.

In horizontal ducts, condensate forms when air is cooled and moisture condenses on the duct surface. Placing drains at the lowest points lets that condensate flow away by gravity to the drain, preventing pooling and leaks. High points would simply collect water, leading to drips, corrosion, or mold. Accessibility matters for maintenance, but the fundamental requirement is drainage from the lowest point, so a drain at a low point is the correct practice. Drains at transition points aren’t about enabling gravity drainage, and while you want access for service, it doesn’t override the need to place the drain at the lowest point.