The Repair vs. Replace Decision Framework
This is the most expensive question in home comfort. Get it wrong and you either waste money on a dying system or replace one that had years of life left. Here's how to decide.
The 50% Rule
If a single repair costs more than 50% of a new system's price and your unit is over 10 years old, replace it. You're essentially paying half the price of a new system to keep an aging one running.
Five Signs It's Time to Replace
1. Age + Frequency of Repairs AC units last 15–20 years, furnaces 20–25 years. If your system is past the midpoint of its lifespan and you're calling for repairs twice a year or more, replacement is the better investment.
2. R-22 Refrigerant (Freon) R-22 was phased out in 2020. Recharges now cost $100–$200 per pound (systems need 5–15 lbs). If your AC uses R-22, replace it—the refrigerant will only get more expensive and harder to find.
3. Rising Energy Bills If your energy bills have climbed 15–25% over 2–3 years despite regular maintenance, your system's efficiency is declining. A new high-SEER system can cut cooling costs by 30–50%.
4. Uneven Temperatures Rooms that are too hot or too cold, despite a working system, indicate the unit can no longer distribute air effectively. This usually means the compressor or blower is failing.
5. Strange Noises or Smells Banging, grinding, or squealing from your system isn't normal. Musty smells can indicate mold in ductwork or a cracked heat exchanger (a safety hazard).
Three Signs Repair Is the Right Call
1. System is Under 10 Years Old A relatively young system is worth repairing unless the repair is a major component (compressor, heat exchanger).
2. Single, Isolated Issue A failed capacitor, blower motor, or thermostat is a straightforward fix. These components don't indicate broader system failure.
3. Repair Cost is Under $1,000 Small repairs on a well-maintained system almost always make financial sense.
The Math: Repair vs. Replace
Here's a practical example:
- Scenario: 14-year-old AC needs a new compressor ($2,800 repair). New system costs $6,000.
- Repair: $2,800 now, but likely 3–5 more years of life with additional repairs ($500–$1,000/year)
- Replace: $6,000 now, but 15–20 years of life with lower energy bills and warranty coverage
- 5-year cost of repair: $2,800 + $3,000 in additional repairs = $5,800, plus higher energy bills
- 5-year cost of replace: $6,000 (covered by warranty), with 30% lower energy bills
In this case, replace wins because the total cost is similar but you get a reliable, efficient system with warranty protection.
Before You Decide: Get a Professional Assessment
A trustworthy HVAC technician will:
- Run a full diagnostic before recommending anything
- Show you the failed component
- Give you honest repair vs. replace advice (even if replacement pays them more)
- Explain efficiency differences between your current system and modern options
Be wary of technicians who push replacement without a thorough inspection.