If a repair costs more than half of a new system and your unit is over 12 years old, replacement usually wins. Here is how we run the numbers with every customer.

Start with the age

Central AC units in Central Texas run 1,800 to 2,400 hours a year. Most reach the end of efficient life between 12 and 15 years, even with good maintenance.

The rule: repair cost × system age > replacement cost → replace. Example: $1,400 repair × 11 years = $15,400, more than an $11,600 system.

Then look at the bill

A 10 SEER unit uses roughly twice the electricity of a modern 17 SEER2 system for the same cooling. On a typical Austin home that gap is $40 to $70 a month in summer.

System age, usually

— Under 8 years: repair

— 8–12 years: run the rule

— Over 12 years: replace