The three-question test
You can get most of the way to the right answer with three questions. First, how old is it? Furnaces typically last 15–20 years in Iowa, air conditioners 12–15, and heat pumps 10–15 — beyond that, failures come faster and parts get scarcer. Second, what does the repair cost against a new system? When one repair crosses roughly one-third of replacement cost on an old unit, the economics flip. Third, is this the first major repair or the third? A pattern of breakdowns is the system telling you something.
Red flags that favor replacement
Some symptoms are worth more weight than others because they signal expensive core failures rather than cheap part swaps.
- A cracked heat exchanger on a furnace — a safety issue, not a repair candidate
- A failed compressor on an AC or heat pump past its warranty
- R-22 refrigerant systems (pre-2010) — the refrigerant is phased out and costly
- Energy bills climbing year over year with no change in usage
- Rooms that never reach temperature, or a system that runs constantly
- Repeated repairs in consecutive seasons
When repair is clearly the right call
Plenty of breakdowns do not justify a new system: igniters, capacitors, flame sensors, blower motors, contactors, and thermostats are routine fixes on systems with life left in them. If your equipment is under about 10 years old and has been maintained, repairing is almost always the smarter money.
This is also where maintenance pays off — True Comfort Savings Plan members get 10% off any HVAC repair, never pay an after-hours fee, and every dime spent on the plan is credited back toward an eventual replacement.
How we keep the recommendation honest
We give you a truly honest assessment — never a high-pressure pitch. You get the repair price and the replacement math side by side, in plain English, and you decide. If replacement does make sense, up to $3,800 off a new system through combined credits, rebates, and discounts often changes the calculation more than homeowners expect.
Frequently asked questions
What is the one-third rule for HVAC replacement?
If a repair costs more than one-third of the price of a comparable new system — and the equipment is in the back half of its expected life — replacement is usually the better investment. Spending $2,500 on a 16-year-old furnace rarely beats putting that money toward a new one.
How long do furnaces and ACs last in Iowa?
With regular maintenance, a gas furnace typically lasts 15–20 years and a central AC 12–15 years in central Iowa's climate. Neglected systems and systems that were oversized or undersized at installation fail years earlier.
Is a cracked heat exchanger worth repairing?
Almost never. A cracked heat exchanger can allow combustion gases, including carbon monoxide, into your home's air. The repair approaches the cost of a new furnace, so replacement is both the safer and the smarter choice.
Can I get an honest opinion without a sales pitch?
That is the core of how True Comfort operates: an honest assessment, your options explained in plain English, and a written fixed price. No high-pressure sales — it's one of our six written guarantees.
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