- R-22 systems are at or near end-of-life — refrigerant is scarce and expensive.
- Systems under 14 SEER (pre-2023 rating) in good repair may still have years left; systems under 14 SEER₂ that need a major repair are strong replacement candidates.
- A Free Second Opinion from Legendary can confirm whether a contractor's replace recommendation is justified.
- New 18–20 SEER₂ systems can cut cooling energy use 30–45% vs. a 12-SEER unit.
Repair is likely the right answer when
The system uses R-410A refrigerant, is under 12 years old, has had only one or two minor repairs, and the current repair quote is under $800 on a system that would cost $5,000+ to replace.
Replacement is likely the right answer when
The system uses R-22, is 15+ years old, has had repeated failures, or needs a compressor replacement (typically $1,200–$2,200, at which point replacement math often wins). Also consider replacing if your home never quite cools — possibly a capacity or efficiency mismatch.
Option A: Repair and continue operating
Right for R-410A systems under 12 years old with an isolated failure. Flat-rate repair pricing from Legendary means no hourly surprises. If the repair restores full function and efficiency, this is the lowest-cost short-term choice.
Option B: Replace with a high-efficiency central AC
A 18 SEER₂ two-stage or variable-speed condenser with a matched coil delivers quieter operation, more humidity control, and significantly lower utility bills. Typical installed cost in North Shore homes: $4,500–$9,000 depending on tonnage and coil/refrigerant line work. ComEd rebates available for qualifying high-efficiency units.
Option C: Replace after this season (plan now, install in fall)
If the system limps through summer but is clearly near end-of-life, plan a fall replacement when contractor scheduling is flexible. Legendary can inspect and confirm the system's health now and schedule a fall installation.
Mismatched coil and condenser
Replacing only the outdoor condenser while keeping an old indoor coil creates a mismatched system that loses efficiency, voids warranties, and may not be rated for R-454B (the newer refrigerant). Legendary always assesses the full system.
Ignoring refrigerant type before repair
Topping off an R-22 system with costly substitute refrigerants or procured R-22 is expensive and short-sighted. Confirm refrigerant type before authorizing any recharge.
Replacing without load recalculation
North Shore homes that have added additions, finished basements, or replaced windows since the original install may need a different tonnage. Always confirm with a Manual J.
Questions homeowners ask
- What refrigerant does my AC use and does it matter?
- R-22 (Freon) is no longer manufactured — if your system uses R-22, recharging is very expensive. R-410A systems are current but are being phased to R-454B in new equipment. Legendary will identify your refrigerant on inspection.
- How much does a new AC cost installed on the North Shore?
- Typical installed range is $4,500–$9,000 for a standard central AC replacement in Lake and Cook County. Variables: tonnage, efficiency rating, coil condition, and refrigerant line work needed. Legendary provides a flat-rate quote before any work begins.
- Will ComEd rebate my AC replacement?
- ComEd offers rebates on central AC systems that meet minimum efficiency thresholds. Rebate amounts change annually. Winnetka Electric customers should check with the Winnetka municipal utility. Legendary identifies applicable rebates at the time of quote.
Editorial provenance
Content by Legendary Service editorial team
Updated:
Methodology
Guidance compares the stated system factors, applicable utility program rules, and the conditions that must be confirmed in the home. Figures are planning ranges, not quotes; Legendary Service provides an upfront flat-rate price after diagnosis.