The size, or capacity, of the heat pump is expressed in either nominal tons or British Thermal Units (BTU). One ton of capacity is equivalent to 12,000 BTU per hour or 3.5 kW. A typical residential heat pump generally ranges between 1 to 5 tons.

In order to receive a heat pump rebate through the CleanBC Better Homes and Home Renovation Rebate Program, your heat pump invoice must indicate the heat pump’s heating capacity as either number of tons or BTUs. If this information is missing on the invoice, contact your contractor and ask them to provide you with an updated invoice with the number of tons. If the contractor listed the capacity in BTU, use the chart below to help you convert from BTU to number of tons.

BTU Number of Tons
12,000 1 Ton
18,000 1.5 Ton
24,000 2 Ton
30,000 2.5 Ton
36,000 3 Ton
48,000 4 Ton
60,000 5 Ton

Example calculation:

  • The heat pump invoice indicates 24,000 BTU.
  • 24,000 BTU ÷ 12,000 BTU/ton = 2 tons.
  • The heat pump has a 2 ton capacity.

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