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Important Units Conversions for HVAC Engineers As Mechanical & HVAC professionals

Important Units Conversions for HVAC Engineers As Mechanical & HVAC professionals, quick unit conversions are essential in daily calculations, troubleshooting, and system design. Here is a quick reference list of commonly used engineering conversions.


LENGTH

  • 1 m = 3.28 ft
  • 1 ft= 12 in = 0.305 m
  • 1 in= 25.4 mm


FLOW

  • 1 L/s =2.12 cfm
  • 1 L/s = 15.85 U.S. gpm
  • 1 L/s = 3.6 m³/h


PRESSURE

  • 1 Bar = 105 Pa
  • 1 Bar = 14.5 psi
  • 1 Bar = 10 m.w.g
  • 1 Bar = 750 mm Hg
  • 1 in.w.g = 249.09 Pa

VOLUME
  • 1 m³ =35.28 ft³
  • 1 m³ = 1000 L
  • 1 U.S. gal = 3.785 L
  • 1 U.K. gal = 4.55 L


MASS

  • 1 kg = 1000 g
  • 1 kg = 35.27 oz
  • 1 kg = 2.2 lb
  • 1 tonne = 1000 kg


TEMPERATURE

  • °C =°K+273.15
  • °F = (°C x 1.8) + 32


COOLING LOAD

  • 1 kW = 3415 Btu/hr
  • 1 RT 3.517 kW
  • 1 RT = 12,000 Btu/hr
  • 1 MBH = 1000 Btu/hr
  • 1 MBH = 0.29 kW

VELOCITY / SPEED
  • 1 m/s = 197 fpm
  • 1 fpm = 1 cfm/ft²

ENERGY
  • 1 Btu = 1055 J

AREA
  • 1 m² = 10.76 ft²

ELECTRIC POWER
  • 1 HP = 0.75 kW


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