Is It Time for a New Furnace or Should I Replace My Furnace’s Heat Exchanger?

December 4, 2017

Have you just been told your furnace has a cracked heat exchanger? You might assume that, as with other furnace parts, you can just replace the heat exchanger and get the system back up and running again without too much trouble.

However, the heat exchanger is the heart of any furnace, making it one of the most expensive parts of the entire unit to repair or replace. If you have a cracked heat exchanger on your hands, use the information here to help you decide if it’s time for a new furnace.

What Is a Heat Exchanger?

The key to heating your home is found in the heat exchanger. When the thermostat detects that the temperature is falling, the furnace flame turns on and heats up the interior of the heat exchanger. This warms up the metal walls and tubing of the heat exchanger before the blower turns on so the air blowing across it picks up as much warmth as possible.

It’s important to understand that air doesn’t flow through the heat exchanger. The heat exchanger is where combustion gases are contained and vented to the exterior after the air passing has absorbed a majority of the heat stored within. Some furnaces feature two heat exchangers to maximize efficiency. The exhaust from a furnace with a dual heat exchanger is cooler, meaning more of the energy your HVAC system consumes is converted into useful heat for your home.

Determine if the Heat Exchanger Is Cracked

It’s sad but true that some unscrupulous HVAC contractors will try to convince you that your furnace heat exchanger is cracked when it’s really in satisfactory condition. This tactic allows dishonest technicians to sell you an expensive repair or entirely new furnace.

Watch out for technicians who attempt the dubious diagnostic method of using water cameras or smoking agents to check for small gaps in the heat exchanger wall. According to the Air Conditioning, Heating, and Refrigeration Institute, heat exchangers are not hermetically sealed, so a tiny bit of leakage is safe and even expected.

If your heat exchanger has really cracked from years of rust and corrosion, the hole will be large enough to see with the naked eye. Other signs of improper combustion caused by a crack in the heat exchanger include:

  • Soot buildup on internal furnace components
  • High carbon monoxide levels in the flue pipe that may leak out and set off your CO detector
  • Flickering yellow or orange burner flames, when they should be steady and blue

Why You Should Replace the Furnace if the Heat Exchanger Is Cracked

It usually takes 18 to 20 years for rust and corrosion to cause a hole to form in a furnace heat exchanger. If your furnace is old enough to have this problem, the heat exchanger probably isn’t worth replacing. Doing so would be comparable to buying a new engine for an old, rundown car.

In most cases, you are much better off putting your money toward a new, high-efficiency furnace replacement. Your investment will provide many immediate and long-term benefits, including:

  • Improved home comfort and humidity levels
  • Better air circulation for more even temperatures from room to room
  • Lower heating bills all winter long
  • Cleaner indoor air
  • Quieter operation

Contact Rick’s Heating & Cooling for Furnace Replacement in the Indianapolis Area

If you’re looking for a second opinion regarding the condition of your heat exchanger, or you’re ready to upgrade to a new, high-efficiency furnace, please contact Rick’s Heating & Cooling today. We are the furnace installation experts for homes and businesses in Southwest Ohio.