A variable speed compressor is an inverter driven compressor that can adjust its operating speed to match a home’s heat demand. Compared to conventional systems, variable speed systems have higher customer satisfaction rates, increased energy savings and less impact on the electrical grid. For these reasons, a variable speed compressor is required for mini-split, multi-split, and Tier 2 central heat pump rebates.

Variable speed compressors are very common in ductless mini-split systems but are available for mid and high-performance central systems as well. Heat pump installers are advised to speak with their equipment distributors about variable speed product options.

General benefits to a homeowner:

  • More consistent indoor temperatures
  • Quieter start-up of the outdoor unit
  • Quieter operation due to increased time operating at low speeds/airflow
  • Lower energy bills and better return on investment

Performance improvements relative to conventional systems:

  • Higher efficiency at partial loads and significant seasonal energy savings, beyond what is captured in the HSPF and SEER ratings
  • Higher capacity in cold weather and a better match to a home’s heating needs
  • Faster defrost cycles
  • At partial load operation, lower airflow requirements mitigate issues associated with high static pressure in existing ductwork
  • Allows equipment to be sized for heating needs, while maintaining high performance in cooling operation.
  • Gradual start-up is easier on equipment
  • Gradual start-up is easier on local electrical grids
  • Increased performance reduces peak energy demand in the heating season