The 5,000 Rule: A Simple Decision Framework

The 5,000 Rule is the most reliable quick test for repair vs. replace decisions: Multiply your system’s age (years) × repair cost ($). If the result is over $5,000, replace.

System Age	Repair Cost	5,000 Rule Score	Decision
5 years	$800	4,000	Repair
8 years	$600	4,800	Repair
10 years	$600	6,000	Consider replacing
12 years	$500	6,000	Replace
15 years	$400	6,000	Replace
15 years	$200	3,000	Repair (marginal)
18 years	$300	5,400	Replace

The 5,000 Rule is a guideline, not a law. Factor in SEER rating, refrigerant type, and condition before deciding.

Additional Factors Beyond the 5,000 Rule

Factor	Lean Toward Repair	Lean Toward Replace
SEER Rating	16+ SEER2	Below 14 SEER (< 15 SEER2)
Refrigerant	R-410A	R-22 (phased out — expensive)
Repair frequency	First major repair	2+ major repairs in 3 years
System age	Under 8 years	Over 12 years
Energy bills	Stable	Steadily increasing
Tax credits available	No	Yes — IRA credits worth $600–$2,000
Home sale planned	No	Selling soon — new system = selling point

Repairs Worth Doing — Cost Guide

Repair	Typical Cost	Worth It If…
Capacitor replacement	$150–$300	Any system age
Contactor replacement	$150–$250	Any system age
Refrigerant recharge	$200–$500	System is under 10 years
Thermostat replacement	$150–$350	Any system age
Condensate drain unclog	$75–$200	Any system age
Blower motor	$400–$700	System under 8 years
Compressor replacement	$1,200–$2,800	Only if system is under 5 years
Heat exchanger	$1,200–$4,000	Never — replace the furnace instead
R-22 refrigerant add	$400–$1,200+	Never — R-22 is phased out; replace system

Signs Your HVAC System Needs Replacement

• Age over 12 years for AC, 18 years for furnace
• R-22 refrigerant (old Freon) — costs $80–$120/lb and getting scarcer
• Compressor failure on a system over 8 years old
• Two or more major repairs in the past three years
• Energy bills rising 20%+ with no explanation
• Frequent on/off cycling (short cycling) — often a sign of oversizing or refrigerant issues
• Visible rust, corrosion, or cracking on heat exchanger

Frequently Asked Questions

What is the ‘5,000 Rule’ for HVAC repair vs replacement?

Multiply your system’s age (in years) by the repair cost. If the result exceeds $5,000, replace the system. Example: a 12-year-old unit needing a $500 repair = 12 × $500 = $6,000 — replace it. A 5-year-old unit needing the same repair = $2,500 — repair it.

How long should an HVAC system last in Los Angeles?

In LA’s climate with proper maintenance, central AC compressors last 12–16 years, air handlers 15–20 years, and gas furnaces 18–25 years. Systems that run without annual tune-ups or with dirty filters often fail 5–8 years earlier.

Is it worth repairing a 15-year-old air conditioner?

Usually not. A 15-year-old system is likely 10–13 SEER (well below California’s 15 SEER2 minimum) and has high operational costs. Unless the repair is minor (under $300) and the system is in otherwise good shape, replacement almost always makes more financial sense.

What HVAC repairs are worth doing vs which signal replacement?

Worth repairing: refrigerant recharge ($200–$400), capacitor ($150–$300), thermostat ($100–$250), contactor ($150–$250). Consider replacing: compressor failure on old system ($1,200–$2,500), heat exchanger crack ($1,000–$3,500+), major refrigerant leak on R-22 system.

Can I get a tax credit for replacing my HVAC system?

Yes. The federal IRA provides a 30% tax credit (up to $600 for central AC, $2,000 for heat pumps) for qualifying high-efficiency replacements. California also has LADWP and TECH Clean CA incentives that can further reduce the cost of replacement.