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Water Heater Sizing Calculator for Contractors
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- Duct Sizing Calculator for HVAC Professionals
Duct Sizing by CFM
400
50
1000
2000
900
400
1200
2000
0.10
0.05
0.15
0.25
100
10
250
500
Round Duct
8 inches
Actual Velocity
900 fpm
Pressure Drop
0.10 in
Rectangular Duct Options
Option 1
8" × 8"
Option 2
10" × 6"
Option 3
12" × 5"
Option 4
14" × 4"
💡 Pro Tip: For residential systems, maintain velocity between 600-900 fpm to minimize noise. Consider using larger ducts for longer runs.
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