There is a point at which continuing to repair an aging system costs more than replacing it. Knowing roughly where that point sits protects you from both mistakes.
Key takeaways
- Repair cost × age in years, against the price of a new system, is the quick test.
- A repair over about a third of replacement, on a unit past twelve years, usually means replace.
- A cracked heat exchanger decides it on its own.
- A cheap fix on equipment with years left is a repair, and we will say so.
From the shop on East Main Street in Church Hill
Where the line usually falls
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The rule of thumb
The rule of thumb worth knowing: multiply the repair cost by the age of the equipment in years. If that number exceeds the cost of a new system, replacement is likely the better call. It is a rough guide, but it captures the right idea — an expensive repair on old equipment is money spent on something that will need spending on again soon.
Repair costAge in yearsCost of a new systemReplacement is likely the better call - 02
A simpler version
A simpler version: if the repair costs more than about a third of a new system and the unit is past roughly twelve years, replacement usually wins once running costs are counted.
Repair over about ⅓ of a new systemUnit past roughly 12 yearsReplacement usually wins - 03
When the arithmetic does not decide it
Some factors override the arithmetic entirely. A cracked heat exchanger means the furnace comes out of service regardless. A system on R-22 with a refrigerant leak is throwing money at a refrigerant that is no longer produced. Repeated failures on the same circuit mean something upstream is wrong.
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And when repair is the right call
And some point the other way. A single failed capacitor on an eight-year-old system is a cheap fix on equipment with years left. Replacing that would be waste, and we will say so.
Failed capacitor, eight-year-old system: repair it.
Decision sheetThe factors that decide it
- Repair cost × age in years, compared against a new system
- Is the repair more than a third of replacement cost?
- Is the equipment past about twelve years?
- Does it use R-22, which is no longer produced?
- Has the same component failed before?
- Are bills climbing year on year for the same comfort?
- Is the heat exchanger cracked? — that decides it on its own
- How long do you plan to stay in the house?
Common follow-ups
Will you tell me if a repair is the better option?
Yes, and we do it regularly. No one here works on commission, so there is no incentive to push you toward the larger number. We will show you the comparison and let you decide.
My system uses R-22. How urgent is that?
Not an emergency, but plan for it. R-22 is no longer produced, so recharging relies on reclaimed stock at rising prices. A leaking R-22 system is the clearest replacement case there is.
Would you like help with your own system?
Free estimates on new equipment. We measure before we quote.
(423) 357-1922