Heat exchanger gasket failure
Heat exchanger gasket failure is the most common cause of a leaking plate unit, and it is usually the seal that has aged rather than anything wrong with the plates.
Tell us about your heat exchanger gasket failure
Five answers, all from memory. The detail comes next, and it is optional.
See the privacy notice for how these details are handled.
Why gaskets fail
Heat exchanger gasket failure is the most common cause of a leaking plate unit, and it is usually the seal that has aged rather than anything wrong with the plates. These are the reasons gaskets fail.
- Age and heat
- Elastomers harden and lose their ability to recover. Temperature drives this far more than years do, so the same gasket lasts very different lengths of time on different duties.
- Compression set
- A gasket held compressed for long enough stops springing back, and once it has taken a permanent set it no longer seals when the pack moves or cools.
- Chemical attack
- Swelling, softening or cracking means the material does not suit the fluid, not that it is old. Refitting the same specification repeats the failure.
- Repeated tightening
- Tightening a weeping pack works for a while and takes the pack closer to the dimension below which it cannot seal at all.
- Damage during assembly
- A gasket that is nipped, twisted or bonded onto a groove that was not cleaned properly will leak early regardless of the material.
What to expect
- Gaskets are replaced as a complete set, because they are all the same age in the same duty, and replacing only the failed ones means another visit shortly afterwards
- The material is matched to the fluid and the temperature rather than copied from what came off
- The pack is opened, so this is the natural point to inspect the plates for cracks
- The pack is rebuilt to its specified dimension, since over-tightening a new set is the most common reason a fresh regasket leaks early
Heat exchanger gasket failure questions
How long should heat exchanger gaskets last?
Temperature and fluid drive gasket life far more than age does. Condition when the pack is opened tells you more than the date they were fitted.
Can I just replace the leaking gasket?
Replacing one gasket is possible and rarely worth it. The rest of the set is the same age in the same conditions, so the next failure is usually not far behind.
Does a gasket failure mean the plates are damaged?
Not usually. Gasket failure and plate cracking are different problems, though the strip down for one is the only chance to check for the other.