The short answer
$800–$4,000
The heat exchanger is the metal wall between the flame and the air you breathe. A crack can let exhaust, including carbon monoxide, into the house air, so the furnace stays off until it’s dealt with. Under the parts warranty you mostly pay labor. Out of warranty the cost nears a new furnace, which is why most owners of a furnace over 10 to 15 years old replace the furnace instead.
Typical industry ranges for Western Washington — not a quote. Your exact price comes upfront, before any work starts, and you approve it first.
What moves the price
Under warranty or not
Many furnace heat exchangers carry a 20-year or lifetime parts warranty, sometimes only if the furnace was registered. Under warranty you pay the labor, typically $800–$1,800. Out of warranty, the part alone often costs $1,000 to $3,000.
It’s a big job
The furnace is taken apart down to the burners and blower to get the old one out. Most take the better part of a day.
The age of the furnace
On a furnace over 10 to 15 years old, a new heat exchanger goes into a furnace whose other parts are all still old. That’s when replacing the furnace usually makes more sense.
Getting the part
A heat exchanger is ordered for your exact model, and older models can be hard to find. Until it’s replaced, the furnace should stay off.
Told your heat exchanger is cracked?
Book a second look. We show you the crack, or tell you it isn’t there. Exact price upfront.
Get My Upfront Quote60 seconds online · or call (253) 766-4822
Typical ranges at a glance
Typical industry ranges for Western Washington — not a quote. Your exact price comes upfront, before any work starts, and you approve it first.
Been told you need a new heat exchanger?
A cracked heat exchanger is the most expensive thing a furnace can be diagnosed with, and one of the most misdiagnosed. Rust, surface scale and the normal seams can look like cracks. A real crack shows on an inspection camera, in a flame that jumps when the blower starts, or as carbon monoxide in the air from the vents. Ask to see it.
We test it and show you the result before anything is replaced. If it tests fine, we say so.
Book a Second LookHow it works
- 1
Book online or call. Tell us what it’s doing, or what you were quoted. We diagnose it ourselves either way.
- 2
We test it and show you what we found. If the part tests fine, it isn’t the problem, and we tell you so.
- 3
You approve the exact price first. Nothing is replaced until you say go.
Where we work
From our base in Covington.
King County
Covington, Kent, Renton, Maple Valley, Black Diamond, Auburn, Enumclaw, Federal Way, Des Moines, Pacific, Algona
Pierce County
Sumner, Bonney Lake, Lake Tapps
Not on the list? Book it anyway and a technician confirms within 1 business hour.
Why homeowners call us
- You approve the price first. Exact price upfront, before any work starts.
- We answer 24/7. A technician reaches out within 1 business hour.
- 500+ jobs done by 4.9★ rated technicians. Licensed & insured.
- Fixed right, guaranteed. If it’s not right, we make it right.
Quick answers
What are the signs of a cracked heat exchanger?
A carbon monoxide alarm going off when the furnace runs, a flame that flickers or lifts when the blower comes on, soot around the burners, an exhaust smell, and headaches or nausea that ease when you leave the house. Some cracks give no sign at all, which is why a yearly tune-up checks for them.
Is a cracked heat exchanger dangerous?
It can be. A crack can let combustion gases, including carbon monoxide, into the air the blower sends through the house. If your CO alarm goes off, get everyone outside and call 911 or your gas utility. Keep the furnace off until it’s been checked.
Can a cracked heat exchanger be repaired?
No. Welding or sealing a crack isn’t an accepted repair. The heat exchanger is replaced, or the furnace is.
Should I replace the heat exchanger or the whole furnace?
If the furnace is under 10 years old and the heat exchanger is under warranty, replacing the heat exchanger usually makes sense. Older than 10 to 15 years, or out of warranty, the repair gets close to the price of a new furnace, and a new one comes with a full warranty. We give you both prices.
How do you check for a cracked heat exchanger?
We look at it with an inspection camera, watch the flame when the blower starts, and test the air coming out of the vents for carbon monoxide. We show you what we find.
Is the heat exchanger covered by warranty?
Often. Many furnaces carry a 20-year or lifetime heat exchanger warranty, sometimes only if the furnace was registered or for the original owner. Labor usually isn’t covered. We check your model’s coverage before quoting.
How long does it take to replace a heat exchanger?
Most of a day once the part is here. It’s ordered for your model, and we tell you the day it arrives.
How do I get my exact price?
Book online or call. A technician reaches out within 1 business hour, tests the part, and gives you the exact price before any work starts. You approve it first.
Ranges are for websites. Quotes are for you.
Book in 60 seconds — a tech reaches out within 1 business hour and your exact price comes before any work.
Get My Upfront Quote60 seconds online · or call (253) 766-4822
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Repair or replace? · New furnace cost · Furnace repair cost · Furnace tune-up · troubleshooting guides