Heat Pump Electrical Requirements (Canada)
Replacing gas heat with heat pumps increases electrical demand. Rule 8-200(1)(a)(iii) and Rule 62-116 govern how heating and cooling loads combine. Use the residential load calculator with correct interlock settings.
Interlocked heat and cooling
When heating and air conditioning cannot operate simultaneously, demand uses the larger load—not the sum. Document the interlock for inspection.
Backup resistance heat
Auxiliary strip heat can exceed heat pump compressor load. Cold-climate installations may require service upgrades beyond what compressor nameplate alone suggests.