The best and number one selling duct sizingtool for Android devices with thousands of happy users. For lessthan the cost of a cardboard wheel ductulator always have a fast,accurate way to analyze ducts for design (by Airflow) or existinginstallations (by Size).Airflow Tab• Calc decimal & rounded sizes for any aspect ratio• Solve for Volume, Aspect Ratio, Friction, or VelocitySize Tab• Calc Friction and Velocity given duct sizeSettings Tab:• Enter various units - Airflow (cfm, m3/s, l/s, m3/hr) Friction(in/100', Pa/30m), Duct Sizing (in, cm), Velocity (ft/min,m/s)• Define standard air - Altitude (ft, meter), Temperature(Fahrenheit, Celsius), Relative Humidity (pct)• Displays calculated Kinematic Viscosity (ft2/s) and SpecificVolume (ft3/lb)Material Types:• PVC• Aluminum• Galvanized Steel• Spiral Steel• Smooth Liner• Fiber Liner• Flex DuctDuct Shapes:• Round• Rectangular• OvalDuct Sizing• Round to Even Units• Round to Odd UnitsCalculations are based on friction loss equations in the ASHRAEHandbook of Fundamentals 2009.Review Notes-----------------------------------------A 12x12 duct matches FPM and CFM when friction is ignored whichdoes not happen in real life. This relationship changes based onthe properties of air (see kinematic viscosity on the settings tab)and on the friction value determined via the type of duct selected.Also, for the times when you want to get friction given CFM andDuct use the "Airflow" tab, select the "ft/min" checkbox and movethe slider accordingly. There are many ways to drive the openvariable.Accuracy:-----------------------------------------Calculations have been verified against ASHRAE fundamentals andseveral other references. There are more input criteria (such asduct material) than velocity, friction, and size mentioned in thereview which the reviewer may not have taken into consideration.Use the Support email link for any questions or concerns.About Powertrade--------------------------Powertrade is the number one developer of mobile HVAC apps withprofessional looking, proven apps in the hands of over 20,000 usersworldwide.Powertrade HVAC Buddy® Applications:-------------------------NEW!HVAC Buddy® Load Calc - Improve accuracy when sizing equipment,demonstrate professionalism on the job, and add substance to yourproposals by using our heat loss and heat gain calculation app.HVAC Buddy® Load Calc (Apple) - Also available on iOS devices -iPhone, iPadHVAC Buddy® - Refrigerant charging and diagnostics.HVAC Buddy® Pressure Temperature - Traditional PT Chart with 71Refrigerants in Metric or Imperial units

Refrigerant PT Chart• 75 Refrigerants• Pressure Units psig/inHg, kPag, kPa, psig, psia, atm, inHg, MPa,barg, bara• Temp Units °F, °C, KelvinTemperature Tab• 1 °F Temperature increments• Bubble and Dew Pressures on same linePressure Tab• 1 psi Pressure increments• Bubble and Dew Temperatures on same lineSettings Tab• Select Pressure Units• Select Temperature Units• Select Refrigerants• Refrigerant PropertiesThank you for looking at HVAC Buddy products. We do our best tomake the best products possible to improve your productivity. Ifyou feel there is any way we can improve please use the contactemail link or support link from within the app.About Powertrade--------------------------Powertrade is the number one developer of mobile HVAC apps withprofessional looking, proven apps in the hands of over 20,000 usersworldwide.Powertrade HVAC Buddy® Applications:-------------------------NEW!HVAC Buddy® Load Calc - Improve accuracy when sizing equipment,demonstrate professionalism on the job, and add substance to yourproposals by using our heat loss and heat gain calculation app.HVAC Buddy® Load Calc (Apple) - Also available on iOS devices -iPhone, iPadHVAC Buddy® - Refrigerant charging and diagnosticsHVAC Buddy® Duct Calc - Powerful tool with a simple to usereal-time interface to help you choose optimal duct sizes.

Make your job easier with our handy refrigerant charginganddiagnostic HVAC app - HVAC Buddy®. If you are servicingequipmentthe best way to begin diagnosis and determine theproperrefrigerant charge is to use HVAC Buddy, a set of gauges, andathermometer. • Superheat for fixed capillary or SubcoolforTXV/EXVsystems • Calculates targeted vs. actual Subcooling •73refrigerants including R-22 (Freon), R-410A (Puron), R-404A,R-134A• Airflow / Delta-T / TEET Calculation • Diagnosis tab forleaks,overcharge, contaminants, etc. • Email System Status Report•Imperial (IP) or Metric (SI) • Use Target Superheat andSubcooltables or enter manually • Fast! Update values realtime withTempand Press sliders • User friendly with several pages of stepbystep instructions if the early outdoor temperature is 75F andyoucharge the system to a “beer can cold” suction line your systemislikely improperly charged. Later in the afternoon hightemperatureswill increase head pressure and the resultingovercharge means alower than desired superheat and wasted energy.Not good! Features:Use HVAC Buddy to enter refrigerant,temperatures, and pressures.The math is done for you to displaySuperheat or SubcoolingTarget,Actual, and Difference. Usetemperature and pressure sliders to seewhat happens in realtimewhen these values change. HVAC Buddycontains generic charts fortarget Superheat and Subcool as well aspressure-temperature tablesfor 71 Refrigerants. Temperature datafor your pressure is displayedon the refrigerant row and changescan easily be viewed by movingthe pressure slider. Add or recoverrefrigerant to get the Actualvalue to within the displayed targetSuperheat or Subcool range.Diagnosis tab - shows common causes forhigh and low superheat,subcooling. Instructions - Several pages ofdetailed step by stepinstructions. Imperial/Metric - View units inFahrenheit/Celsius orpsi/kPa. Airflow - For cooling, compares atargeted differenceacross the coil vs. actual. Also called Delta-Tor Target EvaporatorExit Temperature (TEET). Sliders change valuesin realtime. SystemStatus Report - Use the email tab to createdefaults for emailaddresses, subject, and System Status Reportintroductory text. Tapthe email button and these values areincorporated into a formattedpage including all the parametersrecorded in HVAC Buddy. Edit theemail and / or add contacts. Thenon each service call it's just acouple taps to send a personalizedreport. Note: To accessDiagnostics, Email, and Instructions useyour phones menu button.This app does NOT have a traditional PTChart display. However, youcan view temperatures in the upper lefthand corner given any vaporline pressure (Superheat tab) or Liquidleaving pressure (Subcoolingtab). Accolades and Awards:---------------------------- HVAC Buddyranked #2 inContractingBusiness.com readers choice of top 10contracting apps.HVAC Buddy was featured by the CaliforniaAssociation of HERSRaters and is CalHERS approved!http://calhers.org/ "Very cool app.I can see California reallyrunning with this as we have strictrequirements for verification."- John Richau, Executive Director,Calhers "an excellent programme"- Charlie Richards AboutPowertrade --------------------------Powertrade is the number onedeveloper of mobile HVAC apps withprofessional looking, provenapps in the hands of over 20,000 usersworldwide. Powertrade HVACBuddy® Applications:------------------------- NEW! HVAC Buddy®Load Calc - Improveaccuracy when sizing equipment, demonstrateprofessionalism on thejob, and add substance to your proposals byusing our heat loss andheat gain calculation app. HVAC Buddy® LoadCalc (Apple) - Alsoavailable on iOS devices - iPhone, iPad HVACBuddy® Duct Calc -Powerful, real-time interface to help you chooseoptimal duct sizes.HVAC Buddy® Pressure Temperature - PT Chartwith 71 Refrigerants inMetric or Imperial units.