BoilerTroubleshooting2026-02-10
Boiler Heat Exchanger Failure: Signs and Options
The heat exchanger is the boiler's heart — leaks or cracks here are serious and often decisive.
The heat exchanger transfers heat from the burner to your water. When it fails, repair is costly and replacement is often the better value.
Signs of failure
Persistent leaks traced to the exchanger, repeated pressure loss, kettling that survives flushing, and certain error codes can indicate heat-exchanger trouble.
Repair vs replace
On older boilers, a failed heat exchanger often costs enough that replacing the boiler — with a fresh warranty and better efficiency — makes more sense. We'll give you both options honestly.
Key takeaways
- Exchanger leaks are serious — get them assessed
- Weigh repair cost against boiler age and a new unit
- A new boiler restores warranty and efficiency
- Annual servicing extends exchanger life
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