April 12, 2026

A well-maintained central AC or furnace should last 15-20 years. Before that, most problems are fixable. After that, you're usually throwing money at a lost cause. Here's how to decide. ## The 5,000 rule Multiply the age of your system by the cost of the repair. If it's over $5,000, replace. If it's under, repair. - 12-year-old system, $400 repair → $4,800 → **repair** - 15-year-old system, $600 repair → $9,000 → **replace** ## Hard signs you should replace - **R-22 refrigerant** — phased out since 2020. Refills run $100+ per pound. - **Multiple repairs in the last 2 years** that added up to more than 30% of a replacement - **Rising utility bills** despite no change in usage - **Uneven cooling** that a rebalance/tune-up didn't fix - **System older than 15 years** ## Signs you can probably repair - First major issue after 5-10 years - Frozen coil, clogged drain, capacitor, fan motor — these are all $200-600 fixes - Ductwork problems — those don't require replacing the system - Thermostat issue ## What a new system costs on Long Island - **Central AC** (3-ton, 16 SEER): **$6,000 – $10,000** installed - **Gas furnace** (80-96% efficient): **$5,000 – $9,000** installed - **Heat pump** (air-source, cold-climate): **$8,000 – $15,000** installed - **Full system replacement** (AC + furnace): **$10,000 – $16,000** ## Don't forget the rebates New York's Clean Heat program gives up to **$3,000** back on air-source heat pumps. PSEG also offers rebates on high-efficiency equipment. A good HVAC pro will handle the rebate paperwork for you. --- Need HVAC quotes? [Post your job on LI ToolBox →](/requests/create) and get multiple quotes from local pros in 24 hours.

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