Key Conversion Factors
1 ton = 12 000 BTU/hr = 3.517 kW = 3517 W
1 BTU/hr = 0.000293 kW = 0.2931 W
1 HP (mech) = 0.7457 kW = 745.7 W = 2544.4 BTU/hr
1 MBH = 1000 BTU/hr = 0.2931 kW = 0.08333 tons
Residential HVAC Equipment Capacities
| Equipment | Typical Capacity | BTU/hr | kW | Notes |
|---|---|---|---|---|
| Mini-split (small) | 0.75 ton | 9 000 | 2.64 | Single-room heating/cooling |
| Mini-split (standard) | 1.0 - 1.5 ton | 12 000 - 18 000 | 3.52 - 5.28 | Bedroom or open area |
| Central A/C (small home) | 1.5 - 2 ton | 18 000 - 24 000 | 5.28 - 7.03 | Apartment or small home |
| Central A/C (typical home) | 2 - 3 ton | 24 000 - 36 000 | 7.03 - 10.55 | Most Canadian detached homes |
| Central A/C (large home) | 3 - 5 ton | 36 000 - 60 000 | 10.55 - 17.58 | Large or poorly insulated |
| Gas furnace (small) | 40 000 BTU/hr | 40 000 | 11.72 | Input capacity -- output ~90% |
| Gas furnace (standard) | 60 000 - 80 000 BTU/hr | 60 000 - 80 000 | 17.58 - 23.44 | Most common Canadian furnace |
| Gas furnace (large) | 100 000 - 120 000 BTU/hr | 100 000 - 120 000 | 29.31 - 35.17 | Cold climate or large home |
| Heat pump (air source) | 2 - 4 ton | 24 000 - 48 000 | 7.03 - 14.07 | Capacity at rated conditions |
| Electric baseboard (per unit) | 500 - 2000 W | 1706 - 6824 | 0.5 - 2.0 | Input = output for resistance heat |
| Hot water boiler (residential) | 60 000 - 120 000 BTU/hr | 60 000 - 120 000 | 17.58 - 35.17 | Input; output at 80-95% efficiency |
Commercial and Industrial HVAC Capacities
| Equipment | Typical Capacity (tons) | kW | MBH | Application |
|---|---|---|---|---|
| Rooftop unit (small) | 3 - 5 ton | 10.6 - 17.6 | 36 - 60 | Small retail, office |
| Rooftop unit (standard) | 7.5 - 20 ton | 26.4 - 70.3 | 90 - 240 | Commercial office, school |
| Rooftop unit (large) | 25 - 50 ton | 87.9 - 175.8 | 300 - 600 | Large commercial, industrial |
| Air-cooled chiller (small) | 20 - 75 ton | 70.3 - 263.8 | 240 - 900 | Mid-size office or hospital |
| Air-cooled chiller (standard) | 100 - 300 ton | 351.7 - 1055 | 1200 - 3600 | Commercial buildings |
| Water-cooled chiller | 200 - 2000 ton | 703 - 7034 | 2400 - 24 000 | District cooling, large facilities |
| Commercial boiler | -- | 50 - 3000 | 170 - 10 230 | Heating plant; rated in MBH or kW |
| Fan motor (supply/return) | -- | 0.37 - 75 | -- | 0.5 - 100 HP range |
| Cooling tower | -- | -- | -- | Rated in tons of heat rejection |
HVAC Motor Horsepower Reference
| HP Rating | kW (nominal) | Typical Application |
|---|---|---|
| 1/12 HP | 0.062 | Small circulator pump |
| 1/6 HP | 0.124 | Condensate pump |
| 1/4 HP | 0.186 | Small fan, small pump |
| 1/3 HP | 0.249 | Bathroom fan motor |
| 1/2 HP | 0.373 | Small blower, circulator |
| 3/4 HP | 0.559 | Residential blower motor |
| 1 HP | 0.746 | Residential furnace blower |
| 1.5 HP | 1.119 | Small AHU blower |
| 2 HP | 1.491 | Medium blower |
| 3 HP | 2.237 | Commercial fan / pump |
| 5 HP | 3.729 | RTU supply fan |
| 7.5 HP | 5.593 | Commercial AHU supply fan |
| 10 HP | 7.457 | Large commercial fan |
| 15 HP | 11.19 | Industrial fan / large AHU |
| 20 HP | 14.91 | Large AHU / chiller compressor |
| 25 HP | 18.64 | Large industrial fan |
How to Use the Power Converter
Enter a value in kW, W, BTU/hr, tons, HP, or MBH. All other units update instantly as you type. Use the quick-reference presets to load common Canadian HVAC equipment capacities: standard furnace sizes, A/C tonnage, and motor HP ratings.
The result panel identifies what class of HVAC equipment your power value matches: from a small circulator pump motor to a large chiller plant. This helps verify a converted value is in the expected range before using it in equipment selection or electrical sizing.
Three reference tables cover residential equipment capacities, commercial and industrial HVAC capacities, and HVAC motor HP to kW. Use these to verify converted values against typical equipment ranges and to quickly identify what standard equipment size matches a calculated load.
Use converted capacity values with the Heat Load Calculator and Cooling Load Calculator to compare your building's peak load against standard equipment sizes. Convert efficiency metrics with the SEER / COP / HSPF Converter and COP / EER Converter.
Power and Capacity Units in HVAC -- Complete Guide
Power units in HVAC describe two related but distinct quantities: the rate at which energy is consumed (input power) and the rate at which heating or cooling is delivered (capacity or output). Understanding this distinction -- and converting fluently between kW, BTU/hr, and tons -- is essential for Canadian HVAC equipment selection, electrical sizing, and energy analysis.
BTU/hr and kW -- The Core Conversion
BTU/hr (British Thermal Units per hour) is the standard capacity unit on most North American HVAC equipment. Canadian engineering, electrical sizing, and energy analysis use kilowatts (kW). The conversion: 1 kW = 3412.14 BTU/hr, or 1 BTU/hr = 0.000293 kW. A 60 000 BTU/hr furnace equals 17.58 kW. A 100 000 BTU/hr boiler equals 29.3 kW. For just this conversion, the dedicated BTU to kWh Converter handles both energy and power in these units.
Tons of Refrigeration
The ton is a uniquely North American capacity unit. One ton of refrigeration equals 12 000 BTU/hr or 3.517 kW -- the rate of heat removal required to freeze one ton (2000 lb) of water at 0 degrees C over 24 hours. Residential air conditioners are sold in half-ton increments from 1.5 to 5 tons. Commercial chillers range from 20 to several thousand tons. Canadian building cooling loads are often calculated in kW or BTU/hr and then converted to tons for equipment selection. The dedicated Tons to BTU/hr Converter handles the full range with a reference table.
MBH for Heating Equipment
MBH (thousands of BTU per hour) is widely used for heating equipment -- boilers, furnaces, unit heaters, and radiant systems. A 100 MBH boiler delivers 100 000 BTU/hr or 29.3 kW. Commercial boiler plants often specify capacity in MBH rather than kW because it maps directly to gas input rates on equipment nameplates. When working with Canadian gas utilities, note that gas consumption is billed in GJ (gigajoules), and gas input capacity is often stated in both BTU/hr and kW on Canadian equipment.
Horsepower for Motors
HVAC fan and pump motors are rated in horsepower (HP) in North America. Canadian Electrical Code (CEC) motor branch circuit sizing tables use HP as the primary rating. One mechanical horsepower equals 0.7457 kW or 745.7 W. Common HVAC motor sizes run from 1/12 HP (small circulators) to 25 HP and above (large commercial AHU fans). The motor HP reference table above covers the full residential and commercial range. Always use the nameplate full load amps (FLA) for actual electrical sizing rather than the kW equivalent alone.
Input Power vs. Capacity
A furnace rated at 80 000 BTU/hr input with 95% efficiency delivers 76 000 BTU/hr (22.3 kW) of heat to the space. A 3-ton air conditioner delivers 36 000 BTU/hr (10.55 kW) of cooling while consuming only 3.5-4 kW of electrical input power -- the difference is the heat removed from the refrigerant system and rejected outdoors. This ratio of output to input is efficiency: COP for heat pumps, EER/SEER for cooling systems. Use the COP / EER Converter and SEER / COP / HSPF Converter to work across these efficiency metrics. For annual energy consumption in kWh or GJ, use the BTU to kWh Converter and kWh to MJ Converter.
Frequently Asked Questions
Divide BTU/hr by 3412.14 to get kW. So a 60 000 BTU/hr furnace equals 17.58 kW, and a 36 000 BTU/hr (3-ton) air conditioner equals 10.55 kW. To go the other direction, multiply kW by 3412.14. This is one of the most common conversions in Canadian HVAC since US equipment rates capacity in BTU/hr while Canadian electrical and energy analysis uses kW. Enter any value above and all units convert instantly.
One ton equals exactly 12 000 BTU/hr or 3.517 kW. A 2-ton residential air conditioner delivers 24 000 BTU/hr (7.03 kW) of cooling. A 5-ton unit delivers 60 000 BTU/hr (17.58 kW). Commercial chillers in the 200-500 ton range deliver 703-1758 kW of cooling. For a dedicated tons-to-BTU converter with a full reference table, use the Tons to BTU/hr Converter.
Input power is the electricity consumed by the equipment. Capacity is the heating or cooling delivered to the space. These differ by the equipment efficiency. A heat pump with 3 kW of electrical input and a COP of 3 delivers 9 kW of heating capacity. A 3-ton (10.55 kW capacity) air conditioner might consume only 3.5 kW of input power at rated conditions. Always check whether a specification refers to input or output -- furnace BTU/hr ratings are input, while heat pump BTU/hr ratings are output capacity.
Multiply HP by 0.7457 to get kW. A 5 HP fan motor equals 3.73 kW; a 1 HP furnace blower equals 0.746 kW. For Canadian Electrical Code motor branch circuit sizing, always use the nameplate full load amps (FLA) rather than just the kW equivalent, since motor efficiency and power factor affect actual current draw. The motor HP reference table above covers common HVAC motor sizes from 1/12 HP to 25 HP with kW equivalents.