Plan it

Repair or replace: run the $5,000 rule, then the refrigerant question

A repair averages $350 nationally. A full replacement runs $5,000 to $28,000. That gap is why this decision deserves a day of thought and a second quote, not a signature during the service call.

What is probably happening

The $5,000 rule: multiply the system's age in years by the repair quote. Under $5,000, repair usually wins. Over, replacement starts to make sense. CBS News calls it a starting point, not a verdict.
A second common test: if the repair exceeds 50 percent of the cost of a new unit, or the system is near the end of its life, consider replacing. Central AC systems commonly last 15 to 20 years.
The refrigerant matters. Systems installed before 2025 mostly use R-410A. Since January 1, 2025, new residential AC and heat pump equipment must use refrigerants under 700 GWP, in practice R-454B or R-32. Existing R-410A systems can still be repaired and recharged, but the new A2L refrigerants and parts are not interchangeable with the old system, so a failed major component on an old R-410A unit is usually a like-for-like part, not an upgrade.

Do this in the next five minutes

Find the age. The manufacture date is on the outdoor unit's data plate, often encoded in the serial number.
Do the math: age times the repair quote. Write it down.
Ask what refrigerant it uses. It is on the same data plate.
Ask for the repair quote in writing and a separate replacement quote in writing, from the same contractor, with the readings that justify each.
Get one more quote. Two written repair-versus-replace opinions cost two diagnostic fees.

Do not

Do not replace because 'R-410A is banned'. The 2025 rule restricts manufacturing and importing new high-GWP equipment. It does not ban servicing what is installed.
Do not repair a 20 year old unit for the third time this year without asking for the running total.
Do not accept 'they do not make parts for it' without a part number and a distributor's word.

Who to call

A licensed HVAC contractor, two quotes in writing

The same trade repairs and replaces. The protection is two written opinions and readings, not a different trade.

Get a free shortlist The seven questions for this trade

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What it should cost

$5,000 to $28,000

Full HVAC system replacement, national span, with $7,000 to $20,000 typical for central AC plus furnace in a 2,000 sq ft home. A repair averages $350 and runs $100 to $3,000

Source: CBS News, new HVAC system cost, May 2026, and Angi, HVAC repair cost, August 2026. View source

National published range, not a quote for your job. The full cost table for this trade is on the hvac page.

Ask this contractor, on the phone, before anyone comes out

Tap each one as you ask it.

What diagnostic readings led you to replacement rather than repair?
What refrigerant is in my current system, and what refrigerant would the new one use?
If I repair, what is the part's warranty, and what else on this unit is likely to fail in the next two years?
If I replace, is the quote for a matched system, and does it include a load calculation, permit and old equipment disposal?

End the call if

A replacement quote on the first visit with no diagnostic readings.
A suggestion that you borrow from a lender they recommend.
A refrigerant scare used as the whole argument.

Where this comes from

Not my problem, tap through instead Every hvac answer