AC repair vs replacement: how to decide

At a glance

The age of the system starts the conversation, but it does not settle it. Five things decide most repair-or-replace calls: how old the equipment is, which part failed, what refrigerant it uses, how often it has broken before, and whether the house was comfortable even when it worked.

This guide walks through each factor, gives a decision table you can use with a technician standing in the driveway, and shows how to put a repair quote and a replacement quote side by side without being rushed by a July heat wave.

The five factors that decide it

Each factor below pushes the decision one way or the other. One factor alone rarely settles it; two or three pointing the same direction usually do.

Age. ENERGY STAR says to consider replacement when a heat pump or air conditioner is more than 10 years old, and that a correctly installed high-efficiency unit can save up to 20 percent on heating and cooling costs. Age matters because of what it predicts: older coils, fan motors and electrical parts are closer to their own failures, so one repair is more likely to be followed by another.

The failed part. Electrical parts such as capacitors and contactors are designed to be swapped and are a normal service call. The compressor is the core of the outdoor unit, and the coils hold the refrigerant; failures there are the expensive ones and the ones that should prompt a replacement quote on an older system.

Which failures are small and which are big

The technician's diagnosis is the single most useful piece of information you will get. Ask them to name the part, show the reading or test that identified it, and say whether anything else is close to failing.

Refrigerant: why R-22 changes the answer

Production and import of virgin HCFC-22 (R-22) ended on 1 January 2020; existing R-22 systems may still be serviced with recovered or stockpiled refrigerant. That means any R-22 refrigerant added today comes from a shrinking pool, and the system itself is old by definition: it was built before R-410A became standard.

Under EPA’s Section 608 rules, refrigerant for these systems may be sold only to certified technicians or to employers of certified technicians. You cannot shop for refrigerant yourself, so the price and availability depend on the contractor's supply.

The newer side of the transition matters too. Equipment made or imported since 1 January 2025 uses lower-GWP A2L refrigerants (R-454B or R-32) instead of R-410A. An EPA rule finalized in May 2026, effective 27 July 2026, removed the 1 January 2026 cutoff, so contractors may install pre-2025 R-410A systems until that stock runs out. If your current system is R-410A and fairly young, it can be repaired normally. If you replace it, ask which refrigerant the new equipment uses and confirm the indoor coil is matched to it.

Decision table: what to do in each situation

Find the row that matches your situation. These are starting points for the conversation with a contractor, not fixed rules.

How to compare a repair quote with a replacement quote

Put both numbers on the same page for the same house. Third-party pages publish a 3-ton central AC replacement on existing ducts in DFW at $5,500–$16,500, and a 4-ton at $7,500–$18,500. These are published ranges from other companies, not this site's prices, and your quote depends on equipment, access and what else the job includes.

A fair comparison looks beyond the two totals. The repair quote buys the current system some more time; the replacement quote buys a new system with its own warranty. The questions below make the trade-off concrete.

If you collect more than one replacement quote, line them up in the quote comparison tool so the scope differences are visible, and see the Dallas AC installation cost guide for how the published ranges are built.

Worked example: two hypothetical houses

House 1. Say a 1990s two-story in Plano has a 13-year-old R-22 system that stops cooling in late July. The technician finds a leaking indoor coil. Every factor points the same way: past the ENERGY STAR age marker, a major part, and a refrigerant that is no longer produced. A coil replacement plus R-22 recharge would still leave an old outdoor unit on an obsolete refrigerant, so this is the moment to price a replacement against the published $5,500–$16,500 DFW range for a 3-ton system.

House 2. Now say a 2019 ranch house in Mesquite has an R-410A system that hums but will not start. The diagnosis is a failed capacitor. The system is young, the part is minor, and the refrigerant is current. Repair it, and ask the technician to note anything else that looks worn.

The in-between case. A 10-year-old system with a failed compressor is the hard one. Check the original installation paperwork for the compressor warranty term and whether the equipment was registered; if the part is covered, the repair cost is mostly labor and refrigerant. If it is not covered, get a replacement quote before approving the repair.

When the problem is comfort, not a breakdown

Some systems never break and still never cool the house well. Hot upstairs bedrooms, a clammy feel, or a unit that runs all afternoon in August are often sizing or duct problems. Replacing the outdoor unit with the same size on the same ducts can reproduce the same complaints.

ENERGY STAR estimates that about 20 to 30 percent of the air moving through a typical duct system is lost to leaks, holes and poorly connected ducts. In Dallas homes, many ducts run through a hot attic, so leaks there pull in attic heat. Duct sealing or repair is published in Dallas at $1,300–$8,000 depending on scope (a third-party range, not this site's price).

Dallas enforces the 2021 International Residential Code and 2021 IECC with Dallas amendments, effective 12 May 2023. The IRC requires equipment to be sized from a load calculation (ACCA Manual J) rather than a rule of thumb. If a replacement is on the table, ask for that load calculation rather than "same size as before". The hot and cold rooms guide and ductwork and sealing page cover the diagnosis in more depth.

Evidence to ask for before you decide

1. What exactly failed, and the reading or test that showed it.
2. The age and refrigerant type, read from the data plate on the outdoor unit.
3. Whether other parts show wear: pitted contactor, corroded coil, oil stains at joints, a weak blower motor.
4. Whether the failed part is under the manufacturer warranty, whether labor is covered, and whether the equipment was registered.
5. For a repair: the price, the warranty on that repair, and what is likely to fail next.
6. For a replacement: a load calculation, the AHRI-matched model numbers, the refrigerant, and what the price includes.
7. The contractor's TDLR license number, which must appear on proposals and invoices.

You can check the license yourself with the TDLR lookup walkthrough before approving either job.

Deciding during a Dallas heat wave

DFW averages 20 days a year at or above 100 °F on the 1991–2020 normals, two more than on the 1981–2010 normals. Average first 100 °F day: July 1. Average last: August 27. A breakdown in that window compresses a decision that deserves a week into a single afternoon.

If the house is unsafe to stay in, especially for older adults, infants or anyone with a health condition, approve what restores cooling now. A minor repair that gets the system running through August gives you time to compare replacement quotes in September.

1. Restore cooling first if the fix is minor and the price is clear.
2. Ask for the full diagnosis in writing, including parts that look worn.
3. Get replacement quotes when it is cooler, with a load calculation and model numbers.
4. Compare like for like, using the same scope on every quote.
5. Decide before the next summer, not during it.

Common mistakes

• Recharging a leaking system repeatedly. The leak stays, and each recharge costs again.
• Replacing only the outdoor unit on a mismatched coil. The two are rated as a matched pair; ask for the AHRI combination.
• Buying the same size by default. If comfort was poor, the old size may have been part of the problem.
• Ignoring the warranty. A covered compressor changes the math.
• Counting on expired incentives. The federal Energy Efficient Home Improvement Credit (25C) applied to qualifying property placed in service before 31 December 2025. It is not available for a system installed in 2026.
• Deciding on a single quote. One opinion on a major failure is worth checking.

Sources

• ENERGY STAR, "When is it time to replace?" (retrieved 2026-09-23)
• US EPA, GreenChill regulatory context (archived page) (retrieved 2026-10-20) — verify before relying on it
• US EPA, Section 608 refrigerant sales restriction (retrieved 2026-10-20) — verify before relying on it
• NAHB summary of the EPA final rule (May 2026); EPA AIM Act Technology Transitions program (retrieved 2026-09-23)
• ENERGY STAR, "Duct Sealing" (retrieved 2026-10-20)
• City of Dallas, "Current City Code" (retrieved 2026-09-23) — verify before relying on it
• NWS Fort Worth, "1991–2020 Normals" (retrieved 2026-10-20)
• NWS Fort Worth, "DFW 100° Info" (retrieved 2026-09-23)
• IRS, Energy Efficient Home Improvement Credit (retrieved 2026-09-23)
• Budget Heating, AC replacement cost in Dallas (Dallas, page dated undated) (retrieved 2026-10-20)
• Cold Factor Heating & Air (Flower Mound, TX) (page dated 2026) (retrieved 2026-09-23)
• HVAC Services Pro (DFW) (page dated 2026-04-13) (retrieved 2026-09-23)
• HVAC Services Pro, DFW installation guide (page dated 2026-03-06) (retrieved 2026-09-23)
• HVACProjectCost.com, Dallas page (page dated 2026-08-02) (retrieved 2026-09-23)

Questions

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