Is It Time to Replace Your Furnace? Signs Johnston Homeowners Should Watch For

Repair or Replace? How to Decide

Nobody wants to spend thousands on a new furnace. But continuing to pour money into a failing system can cost you even more in the long run. Here are the signs Johnston homeowners should watch for when deciding whether to repair or replace.

Your Furnace Is Over 15 Years Old

The average furnace lifespan is 15–20 years with proper maintenance. If yours is in that range and requiring more frequent repairs, replacement is usually the smarter investment. Plus, today's high-efficiency furnaces use significantly less gas than models from 15+ years ago.

Repairs Are Getting More Frequent and Expensive

A good rule of thumb: if a repair costs more than 50% of the value of a new system, replace it. Also consider the trend — if you've had two or three repairs in the past two years, the next one is probably just around the corner.

Your Energy Bills Are Climbing

If your gas bills have been rising despite stable utility rates, your furnace is likely losing efficiency. Older furnaces naturally degrade over time, especially if maintenance has been inconsistent. A new 96% AFUE furnace can reduce your heating costs by 20–30% compared to an older 80% model.

Uneven Heating Throughout Your Home

If some rooms are too warm while others are chilly, your furnace may be struggling to distribute heat evenly. This can be a ductwork issue, but in older systems, it often means the furnace no longer has the capacity to keep up with your home's heating demands.

Strange Noises

Banging, rattling, squealing, and popping sounds aren't normal. While some noises indicate minor issues, others — like a cracked heat exchanger or failing blower motor — signal serious problems that may not be worth fixing on an aging system.

Yellow Burner Flame

A healthy furnace burner produces a steady blue flame. A yellow or flickering flame can indicate incomplete combustion, which may produce carbon monoxide. This requires immediate professional attention.

Not sure where your furnace stands? Trade Allies Heating and Cooling offers honest assessments with no pressure to buy. We'll tell you if a repair makes sense or if it's time for an upgrade. Call (515) 669-4481 for a free evaluation.