KEEN Ductulator

ASHRAE-based duct sizing tool for heat pump systems

1Duct Requirements

2Recommended Sizing

Recommended Round Duct
Meets velocity and friction limits
Velocity
Friction Loss
per 100 ft of duct
Equivalent Rectangular Duct

3Duct Size Comparison

Duct Size Area (sq ft) Velocity (FPM) Friction (in. w.g./100 ft) Status

4Rectangular Duct Equivalents

Aspect Ratio Equivalent Dimensions Equivalent Diameter (in.)

5Static Pressure Analysis

System ESP Available
0.25
in. w.g.
Pressure Drop (Duct Run)
—
in. w.g.
Remaining Available Static
—
Fitting Equivalent Lengths Reference ▼
Fitting Type Equivalent Length (ft)
90° Elbow (round) 15 ft
45° Elbow (round) 8 ft
Tee (branch) 20 ft
Takeoff 10 ft
Register Boot 35 ft
Filter Grille 45 ft

6Multi-Run Calculator

Size multiple duct runs for the same system

R-454B Refrigerant Safety Guidelines ▼
KEEN systems use R-454B (A2L, mildly flammable) refrigerant.

Per ASHRAE 15 and manufacturer guidelines:
• Ensure adequate ventilation in mechanical spaces
• Follow local codes for refrigerant line routing near ductwork
• Consult KEEN installation manual for specific clearance requirements
• Never puncture or damage refrigerant lines
• Only licensed technicians should handle refrigerant

KEEN Ductulator v1.0 • ASHRAE-based calculations • Works offline