Chicago's Energy Challenge

Chicago has one of the most demanding climates in the country for HVAC systems. Winters regularly drop below 0°F, and summers push into the 90s with high humidity. Your HVAC system runs hard for 8–9 months of the year. Small efficiency improvements add up significantly over a Chicago heating and cooling season.

Thermostat Strategy: The Biggest Free Win

Thermostat setbacks are the single most impactful no-cost energy saving strategy. Every degree you lower the thermostat in winter saves approximately 1–3% on heating costs. Every degree you raise it in summer saves a similar amount on cooling.

• Winter: Set to 68°F when home and awake, 60–65°F when sleeping or away. A programmable or smart thermostat automates this.
• Summer: Set to 76–78°F when home, 82–85°F when away. Each degree above 72°F saves 3–5% on cooling costs.
• Smart thermostats (Lennox iComfort, Ecobee, Honeywell T6) learn your schedule and optimize setbacks automatically. They typically pay for themselves in 1–2 years through energy savings.

Maintenance: Keep the System Running Efficiently

• Change the air filter regularly. A clogged filter forces the system to work harder, increasing energy use by 5–15%.
• Annual professional tune-up. A clean, properly tuned furnace or AC runs more efficiently. A dirty burner or low refrigerant charge wastes energy.
• Keep the outdoor condenser clean. A dirty condenser coil reduces AC efficiency by 10–30%. Annual coil cleaning is part of a professional tune-up.
• Seal duct leaks. Leaky ductwork in unconditioned spaces (attic, crawlspace, unheated basement) can waste 20–30% of conditioned air. Duct sealing is one of the highest-ROI energy improvements for older Chicago homes.

Equipment Upgrades: When They Make Sense

• High-efficiency furnace (96%+ AFUE): Replacing an 80% AFUE furnace with a 96% AFUE model reduces heating fuel use by about 17%. In Chicago, where heating season is long, this payback is typically 5–8 years.
• High-SEER air conditioner (18+ SEER2): Replacing a 10 SEER unit with an 18 SEER2 model cuts cooling energy use nearly in half. Payback depends on cooling usage but is typically 6–10 years.
• Variable-speed equipment: Variable-speed furnaces and air handlers run at lower speeds for longer periods, which is more efficient than single-speed equipment that cycles on and off. They also provide better humidity control and more even temperatures.
• Whole-home humidification: Properly humidified air feels warmer, allowing a 2–4°F thermostat setback in winter. This can offset the cost of running the humidifier.

Building Envelope: The Foundation

No HVAC upgrade saves as much energy as a well-insulated, well-sealed building envelope. Chicago's older housing stock — bungalows, two-flats, greystones — is often under-insulated by modern standards.

• Attic insulation to R-49 to R-60 is the highest-ROI insulation upgrade for most Chicago homes
• Air sealing (attic bypasses, rim joists, penetrations) reduces infiltration and heating/cooling load
• Window replacement has a long payback but improves comfort significantly in Chicago winters

D's Air & Heating can assess your HVAC system's efficiency and recommend upgrades appropriate for your home and budget. Contact us for a free estimate.