Calculated Industries 4090 Sheet Metal/HVAC Pro Calculator — Underwood Distributing Co. Skip to content
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4090 Sheet Metal/HVAC Pro Calculator

SKU Calc_4090
Original price $89.95
Original price $89.95 - Original price $89.95
Original price $89.95
Current price $84.95
$84.95 - $84.95
Current price $84.95

Quantity discounts available! Email

Advanced Construction-Math Calculator for Sheet Metal, HVAC

The Sheet Metal/HVAC Pro Calc is designed for sheet metal workers and HVAC technicians to simplify dimensional math, geometry, trig, and has custom HVAC functions all in one simple-to-use and versatile tool for skilled tradesmen.

Sheet metal calculations

  • X, Y, R (radius)
  • Theta
  • Seg Radius
  • Converts between Polar and Rectangular Coordinates
  • Offset functions determine "S"- shaped bends in ductwork

Additional features

  • Order of operation
  • Parenthesis operators
  • Square, cube, square root, and cube root calculations
  • Works as a regular calculator
  • Backspace key for last entry editing

Trigonometric functions

  • Sine, Cosine, Tangent, Arcsine, Arcosine, and Arctangent
  • ArcK Constant
  • Calculates non-90° triangles

Built-in HVAC formulas

  • Fan Law Functions for Test and Balance (TAB)
  • Velocity
  • Velocity Pressure
  • Advanced construction-math functions
  • Work in and convert between building dimensional formats: feet, inch, fractions, and metric
  • Calculate instant areas and volumes
  • Perform square-ups, slopes, rafters, and more
  • Determine regular, irregular hip/valley rafter lengths plus plumb, level, and cheek cut angles
  • Perform complete stair layouts
  • Find circle, column/cone surface area, and volume solutions
  • Complete D:M:S to decimal degree conversions


  • Rugged shock, dust, and moisture-resistant Armadillo Gear case, and a protective slide cover
  • Quick reference guide and complete easy-to-follow user's guide
  • 2 Long-life batteries (LR-44)
  • One-year limited warranty

Tech Specs

  • Size: 5.6" x 3.0" x 0.5" (142mm x 76mm x 13mm)
  • Product Weight: Calculator only 3.2 oz. (91gm)
  • Power: Two 1.5 volt (LR 44) Long-life Batteries
  • Display Type: LCD
  • Display Dimensions: 2.5"L x 0.75"W (64mm x 19mm)
  • Accuracy: 12 Digit Internal Accuracy
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