Labconco Protector XL 1124 Series User Manual page 77

Original instructions
c. Free opening area
2. Determining bypass or "leakage" area
a. This is the opening width (A) times 2.2 inches (A x 2.2 = bypass area).
b. Divide this by 144 to arrive at square feet
3. Determining Total Effective Opening Area
a. This is the Free Opening Area plus the Bypass Opening Area
Model numbers beginning 112 (continued)
Horizontal sashes (Sashes that move left and right)
1. Determine the free opening area
a. Width
b. Height
Product Service 1-800-522-7658
Appendix G: VAV Floor-Mounted Open Area Guidelines
i. Multiply the width opening times the vertical opening (A x B),
and enter that here:
Free opening area = _____________ square inches = C (sq in)
ii. Divide this by 144 to arrive at square feet, and enter that
here:
Free opening area = ____________ square feet = C (sq ft)
Bypass area = ___________ square inches = D (sq in)
Bypass area = ____________ square feet = D (sq ft)
(C + D = Total Effective Opening Area)
Total Effective Area = _____________ square inches
Total Effective Area = _____________ square feet
i. Measure the opening between sashes and
enter that here:
Width Opening ___________ inches = A
i. Measure the vertical distance between the top of the sash
track and bottom of the header panel, and enter that here:
Vertical Opening _____________ inches = B
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