Should you replace your heat exchanger or get a new furnace?

Have you gotten the bad news recently that your furnace’s heat exchanger is cracked and therefore you need a new one?


Now you’re left with a tough decision: replace the heat exchanger or save money in the long run and just replace the furnace.

Well, before we answer that, can we be honest?

Your heat exchanger may not be cracked and you may be getting scammed.

Warning: Watch out for this heat exchanger scam

Some dishonest contractors out there will say that your heat exchanger is cracked to scare you into paying and arm and leg with them.

They’ll show you these “cracks” by showing you how water or smoke gets through gaps in the heat exchanger.

But that’s a trick.

Heat exchanger are not sealed airtight, meaning that a little bit of water or smoke is bound to get through.

According to the Air Conditioning, Heating and Refrigeration Institute (AHRI):
“Any crack or hole that is big enough to affect combustion will be easily visible to the naked eye. DO NOT use water or smoking agents to check for leaks. Furnace heat exchangers joints are not hermetically sealed, so a small amount of leakage is normal.” (Emphasis ours)

So, if your HVAC contractor says you have a cracked heat exchanger, ask him or her to show you the crack. You can see it.

OK, let’s say the crack is legit. Let’s answer your initial question: replace the heat exchanger or replace the entire furnace?

Two key factors: Furnace age and warranty

Is your furnace about 15-20 years old? Does your warranty NOT cover the parts heat exchanger?

If you said  “yes” to both, you should probably replace the furnace. Putting a new heat exchanger into an old-as-dirt furnace is like putting a new engine into an old-as-dirt car.

And if the parts warranty does not over the heat exchanger, you’re going to pay a boatload of money. So much so that getting a new furnace makes more sense financially.

Therefore, finding a new furnace is your next step.

How to find a furnace that’s worth your money

Alternatively, you can contact Santa Fe Heating and Air for furnace advice. We’ve been helping Olathe, Overland Park, Gardner, Lenexa and metro Kansas City homeowners since 1987.