How to Use the All-in-One HVAC Converter
Each panel converts independently. Type a value into any field within a panel and all other fields in that panel update instantly. Each panel works completely on its own -- changing the temperature panel doesn't affect the pressure panel.
Each panel has a row of preset chips for the most common Canadian HVAC reference values: Calgary and Toronto design temperatures, standard furnace static pressure, common cylinder sizes, and more. Tap a chip to load the value and see all units instantly.
Each panel has its own Clear button so you can reset one section without losing work in the others. This is useful when working on multiple conversions simultaneously -- for example, checking a pressure reading while converting a capacity figure in a different panel.
Each panel has a "Full converter" link that takes you to the dedicated tool for that unit category. The full tools include additional units, built-in sub-calculators (ACH, flow-from-heat-load, envelope heat flux), and reference tables. Use this all-in-one page for quick daily conversions; use the dedicated tools for detailed work.
Why Canadian HVAC Needs a Multi-Unit Converter
Canadian HVAC is a dual-unit environment. Building codes and provincial regulations specify requirements in metric: kPa, kW, L/s, and metres, per the National Building Code of Canada. Equipment manufactured in North America is labelled in Imperial: psi, BTU/hr, CFM, and inches. Older Canadian drawings use Imperial. European equipment uses SI. A Canadian technician on any given day might read a pressure gauge in psi, check a furnace nameplate in BTU/hr, verify a ventilation rate in L/s against a code specification, and convert a pipe diameter from inches to millimetres for a drawing. Having all these conversions in one panel -- without switching tabs or pages -- makes the whole workflow faster.
Temperature Conversion in HVAC
The Celsius-to-Fahrenheit conversion (°C x 1.8 + 32) comes up constantly. Canadian design temperatures are specified in °C: Calgary winter design is -29°C, Toronto summer design is 33°C, and standard indoor comfort is 21°C. The Design Temperature Lookup covers these values for every Canadian city. US equipment technical manuals and some manufacturer data show the same conditions in °F (-20.2°F, 91.4°F, and 69.8°F respectively). The temperature panel above handles both directions instantly. For the full tool including Kelvin, Rankine, and specific HVAC reference tables, use the Temperature Converter.
Pressure Conversion: Pa, kPa, psi, and inWG
Pressure units in HVAC span an enormous range of applications. Fan static pressure uses inWG (0.1 to 3 inWG) and Pascals (25 to 750 Pa). Refrigerant system pressures use kPag or psig (200 to 4000 kPa, 30 to 580 psi). Atmospheric pressure references use kPa (101.3 kPa standard). Blower door test pressure is 50 Pa (0.2 inWG), the standard reference point used by the Blower Door Calculator for airtightness testing. All four units are in the pressure panel here; the Pressure Converter adds mmHg, atm, and gauge-vs-absolute context.
Power and Cooling Capacity
The power panel handles the four most common HVAC capacity units: kW (engineering and Canadian electrical), BTU/hr (North American equipment labels), tons of refrigeration (equipment marketing and commercial specs), and MBH (commercial HVAC submittals). The fixed relationships -- 1 ton = 12 000 BTU/hr = 3.517 kW = 12 MBH, derived from the exact BTU-to-watt factor in the NIST Guide to the SI, Appendix B -- are worth memorising, but having them in a converter speeds up equipment comparison and load calculation work considerably.
Frequently Asked Questions
Seven conversion panels: temperature (°C, °F, K), pressure (Pa, kPa, psi, inWG, bar), airflow (CFM, L/s, m³/h, L/min), power and cooling capacity (kW, BTU/hr, tons, HP, MBH), energy (kWh, MJ, GJ, BTU), length (mm, cm, m, in, ft), and mass (kg, lb, g, oz). Each panel is live and independent -- enter any value in any panel and all fields in that panel update instantly.
Canadian HVAC mixes units constantly. Codes and engineering use metric (kPa, kW, L/s, metres). Equipment made in North America is labelled in Imperial (psi, BTU/hr, CFM, inches). Technicians convert pressure gauge readings in psi to kPa, fan airflow in CFM to L/s for ventilation compliance, equipment capacity in BTU/hr to kW for electrical sizing, and pipe dimensions in inches to millimetres for drawings -- often in a single job. Having all conversions on one page eliminates the overhead of switching between tools.
Multiply °C by 1.8 then add 32. So 21°C = (21 x 1.8) + 32 = 37.8 + 32 = 69.8°F. To go the other way, subtract 32 then divide by 1.8. Quick Canadian HVAC references: -29°C (Calgary winter design) = -20.2°F; 33°C (Toronto summer design) = 91.4°F; 21°C (indoor comfort setpoint) = 69.8°F; -40°C = -40°F (where the two scales cross).
1 ton of refrigeration equals 3.517 kW or 12 000 BTU/hr. A 2-ton unit delivers 7.03 kW and 24 000 BTU/hr. A 3-ton unit delivers 10.55 kW and 36 000 BTU/hr. Enter any tonnage in the Power & Capacity panel above to see kW, BTU/hr, HP, and MBH equivalents simultaneously. For a full reference table from 1 to 1000 tons, use the Tons to BTU/hr Converter.