Hey, I’m Chris, owner and lead inspector for Wiemann Home Inspection. Over the last 10 years since joining the team here, my team and I have crawled through thousands of attics, basements, and crawlspaces across the Midwest. While charming historic homes and established neighborhoods are a major draw in our region, (they’re some of my favorite homes to inspect), they often come with alot of hidden surprises. Old furnaces and air conditioners – well, they’re old and you need to take that in consideration when buying a home.

In our midwest climate, heating and cooling equipment doesn’t just sit there. It works overtime. From scorching, humid July afternoons to sub-zero January blizzards, these systems endure extreme thermal cycling. When we’re evaluating a property for a home buyer, the HVAC system is one of the biggest ticket items we inspect.

Common Red Flags in Older Systems

• Terminal Heat Exchanger Cracks: On old gas furnaces (15–20+ years), the metal heat exchanger frequently develops stress fractures from constant expansion and contraction. This is a critical safety hazard, as it can leak odorless carbon monoxide into the home.

• Boiler Kettling and Corrosion: Classic cast-iron boilers can last 25 to 35 years, but they are prone to neglect. I look for mineral scale buildup causing “kettling” (rumbling noises), rusted relief valves, and leaking distribution pipes.

• Obsolete Refrigerant (R-22): If the central air conditioner is over 15 years old, it likely runs on Freon (R-22). Because this refrigerant is phased out and no longer produced, even a minor leak repair can cost hundreds or thousands of dollars to fix.

• Short Cycling and Failing Igniters: Old furnaces that fire up constantly and shut down quickly are burning through extra fuel and wearing out their control boards prematurely.

A system that simply turns on during a walk-through does not mean it’s in good health. If you are buying a home in the Midwest, knowing the exact age and remaining life expectancy of your mechanicals gives you massive leverage during price negotiations. Let my team take the guesswork out of your investment by scheduling your inspection with one of our team members today.