Repair or Replace Your Air Conditioner?

Every HVAC company has a rule of thumb for this, and most of them are quietly tilted toward replacement. Here’s the actual calculation, so you can check the recommendation you’re given.

The basic test

Multiply the age of the system in years by the cost of the proposed repair. If the result exceeds roughly 5,000, replacement is usually the better spend. A $400 repair on a 6-year-old unit gives 2,400 — fix it. A $900 repair on a 15-year-old unit gives 13,500 — that money belongs in a new system.

It’s a rough instrument, not gospel. But it’s a useful sanity check on any quote.

What changes the answer

R-22 refrigerant

Systems installed before roughly 2010 typically use R-22, which has been phased out of production. Recharging one is expensive and getting more so. If an R-22 system has a leak, replacement almost always wins — the refrigerant alone can approach the cost of a meaningful chunk of a new system.

Compressor failure

The compressor is the single most expensive component. On a system past ten years, a failed compressor is generally the end of the road. Under warranty and under eight years, it may not be.

How long you’re staying

Efficiency gains pay back over years. If you’re selling in eighteen months, the payback never arrives and a competent repair is the rational choice.

Whether the furnace is also aging

If both are near end of life, replacing together costs less than replacing separately — one labour charge, and a matched system that hits its rated efficiency instead of a mismatched pair that doesn’t.

The question to ask

Ask for both numbers in writing: the repair cost, and the replacement cost. Any contractor who won’t price the repair because they’d rather sell the replacement has answered a different question than the one you asked.