HVAC/R Unit Converter for Fast, Accurate HVAC Calculations
Use DuctArchitect to convert airflow, cooling capacity, power, pressure, water flow, and heat transfer units in one place. Access clear conversion formulas and reference values to simplify HVAC calculations and support accurate engineering decisions.
Simplify Airflow Calculations with Quick Unit Conversions
DuctArchitect helps you convert airflow rates and air velocity between CFM, CMH, L/s, FPM, and m/s, making HVAC calculations quicker and supporting efficient system design.
Manage HVAC Project Costs and Track Your Field Team in One Place
DuctArchitect connects BOQ management, material planning, employee tracking, and project workflows to help HVAC businesses control costs and coordinate field operations.
BOQ & BOM Management: Plan quantities and material requirements for every HVAC project.
Employee Tracking: Monitor attendance, field activity, and site locations.
Project Management: Assign tasks and track project progress, responsibilities, and timelines.
Inventory Control: Manage materials, supplier orders, and stock movement alongside project work.
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HVAC Capacity and Power Converters
Convert cooling capacity, thermal output, and mechanical horsepower into the units you need for accurate HVAC calculations.
- TR to kWtons of refrigeration to kilowatts of cooling capacity
- TR to BTU/hrtons of refrigeration to British thermal units per hour
- kW to BTU/hrkilowatts of thermal capacity to British thermal units per hour
- kcal/hr to TRkilocalories per hour to tons of refrigeration
- MBH to kWthousand BTU per hour to kilowatts
- HP to kWmechanical horsepower to kilowatts
Convert Pressure Readings and Water-Flow Rates with Confidence
DuctArchitect converts inches WG to Pa, psi to kPa, and GPM to L/s, helping HVAC professionals compare pressure and water-flow values for clearer, more efficient calculations.
Heat transfer
Frequently asked questions
What Does the R in HVAC/R Mean in Mechanical Services?
HVAC/R stands for heating, ventilation, air conditioning, and refrigeration. The term covers building climate-control systems as well as refrigeration applications used to cool spaces and preserve products or materials.
What Is Air Velocity, and Why Does It Matter in HVAC Duct Design?
Air velocity is the speed at which air moves through a duct, usually measured in feet per minute (FPM) or metres per second (m/s). It affects friction-related pressure losses, system noise, and fan energy consumption. Excessive velocities can increase noise and pressure losses, while lower design velocities may require larger ducts to carry the same airflow. Appropriate velocity limits depend on the duct layout and system design requirements.
How Do Professionals Calculate and Measure Air Velocity in HVAC Ventilation Ducts?
Professionals calculate average air velocity by dividing the volumetric airflow rate by the duct's internal cross-sectional area. The formula is V = Q ÷ A, where V is velocity, Q is volumetric airflow, and A is duct area. Using airflow in m³/s and area in m² gives velocity in m/s.
During commissioning and site inspections, technicians use anemometers to measure actual air velocity and compare their readings with design requirements. DuctArchitect's Duct Sizing feature calculates duct dimensions using airflow and friction-loss requirements, while actual field measurements require suitable instruments.
How Do Engineers Calculate the Mass Flow Rate of Air in kg/s?
Engineers calculate the mass flow rate of air by multiplying volumetric airflow by air density at the relevant operating conditions. The formula is ṁ = ρ × Q, where ṁ is mass flow rate, ρ is air density, and Q is volumetric airflow. To obtain a result in kg/s, use air density in kg/m³ and volumetric airflow in m³/s.
Air density varies with temperature and pressure, so the calculation must use appropriate operating conditions. A mass air flow rate unit converter would convert an existing mass-flow value between supported units, whereas calculating mass flow from volumetric airflow requires air-density data and a separate calculation. This page does not provide a dedicated mass airflow converter.
How Do Technicians Convert Volumetric Airflow to CFM?
Technicians convert volumetric airflow to cubic feet per minute (CFM) by applying the appropriate conversion factor to the original measurement. To convert litres per second (L/s) to CFM, multiply by approximately 2.119. To convert cubic metres per hour (m³/h) to CFM, multiply by approximately 0.589.
For example, 100 L/s is approximately 211.9 CFM. A unit converter for flow rate helps technicians compare fan schedules and equipment specifications expressed in different units. Always check the original air flow rate unit before converting, and remember that a converted value alone does not confirm whether a fan or duct is correctly sized.
How Do You Compare AC Cooling Capacity in BTU/h, TR, and kW?
You can compare known cooling-capacity ratings by converting them into a common unit. One refrigeration ton (TR) equals 12,000 BTU/h, or approximately 3.517 kW. One kW of cooling capacity is approximately 3,412.14 BTU/h.
An AC unit BTU calculator estimates the required cooling capacity using room and building information, whereas unit conversion expresses an existing rating in another unit. The distinction matters because converting a manufacturer's rating does not establish whether the equipment can meet a building's cooling load.
Can Room Area in Square Metres Be Converted Directly into AC Cooling Capacity in BTU/h?
No, room area in square metres cannot be converted directly into cooling capacity in BTU/h because area and cooling capacity are different physical quantities. Determining the required capacity involves room dimensions, ceiling height, insulation, window areas, solar exposure, occupancy, and other factors affecting heat gain.
An AC unit size calculator estimates the required capacity from relevant room and building inputs, rather than floor area alone. Similarly, an air conditioner room-size calculator in kW estimates the required thermal capacity, not a direct conversion from square metres. This page helps users compare known capacity ratings but does not calculate the cooling requirement of a room.
How Does a Heating BTU Calculator Differ from a Unit Converter?
A heating BTU calculator estimates the heating capacity a building requires from factors such as building dimensions and heat loss, while a unit converter expresses an existing heating-capacity value in another unit. For example, you can convert a known rating from BTU/h to kW by dividing the BTU/h value by approximately 3,412.14.
The conversion does not determine the heating load of the building. Use the appropriate engineering calculation to establish the requirement, then convert the resulting rating when comparing equipment specifications.
Can CFM, FPM, and kg/s Be Converted Directly into One Another?
No, these units describe different physical quantities. CFM measures volumetric airflow, FPM measures air velocity, and kg/s measures mass flow rate. Converting between them requires the appropriate additional information or calculation.
For example, calculating air velocity from volumetric airflow requires the duct's internal cross-sectional area. Calculating mass flow from volumetric airflow requires air density. Identifying the correct quantity before selecting a conversion prevents misleading comparisons between HVAC measurements.
What Does an HVAC Unit Conversion Tool Do, and When Is a Separate Engineering Calculation Needed?
An HVAC unit conversion tool expresses a known measurement in another unit without changing the underlying physical quantity. An HVAC unit converter or HVAC conversion calculator can help compare existing values when the relevant conversion is supported.
Engineering calculations serve a different purpose. Determining mass flow, cooling requirements, or duct dimensions requires appropriate inputs and calculation methods, rather than unit conversion alone. Always check which conversions the specific tool supports before relying on it for technical work.
When Should Technicians Use an HVAC Imperial-to-Metric Converter?
Technicians use an HVAC imperial to metric converter when drawings, equipment submittals, or commissioning records use different measurement systems. Examples include converting duct dimensions from inches to millimetres, airflow from CFM to L/s, or velocity from FPM to m/s.
The conversion must preserve the original physical quantity and use the correct factor. Technicians should also retain unit labels and suitable precision when transferring values into project documents, equipment schedules, or technical reports.
What Should You Check Before Using an HVAC Measurement Converter?
Before converting a measurement, confirm the physical quantity, the original unit, the target unit, and the applicable conversion factor. An engineering unit converter can help express technical values consistently, but it cannot verify whether the original design measurement is correct.
Keep the unit label with the converted result and use appropriate precision for the intended application. For calculations involving air density or other operating conditions, confirm that the inputs match the relevant conditions before relying on the result.