Reducing summer cooling costs

Shade, airflow, humidity and equipment condition — the levers that reduce cooling load before the thermostat setting even matters.

Last reviewed 2026-07-15 · About 6 min read

Cooling cost is a function of how much heat enters the house and how efficiently the system removes it. Most homeowners adjust only the thermostat, which is the last lever, not the first.

Stop heat before it enters

West and south-facing glass is usually the largest daytime gain. Exterior shading outperforms interior blinds, but closing blinds on sun-facing windows still helps measurably.

Attic temperature drives ceiling gain; ventilation and insulation both matter here.

Help the equipment do its job

Clear vegetation and debris from the condenser, clean the coil, keep filters fresh, and confirm the condensate drain is not backing up.

Use fans correctly

Ceiling fans cool people, not rooms. They allow a higher thermostat setting while remaining comfortable, but running them in empty rooms only adds heat and cost.

Manage humidity

Humid air feels warmer. Running bath and kitchen exhaust during and after use, and correcting crawlspace or basement moisture, improves comfort at the same temperature.

When to call a professional

  • The system runs continuously without reaching setpoint
  • There is ice on refrigerant lines or the indoor coil
  • You suspect low refrigerant charge — this is not a DIY repair

Source notes

  • Estimate basis