Air Leakage & Cross-Contamination in Cores

Two streams, one box

Every recovery device brings exhaust and supply into one casing. The question is whether they can mix. Leakage is the fraction of one stream that escapes into the other through seals, the matrix or carryover.

How the technologies compare

• Plaque (sensible): streams separated by solid walls; leakage is only through perimeter seals, effectively zero mixing.
• Caloduc: also fully separated – ideal for dirty or hazardous exhaust.
• Rotary wheel: matrix is shared, so some carryover is unavoidable; a purge sector reduces but does not remove it.

The selection rule

For laboratories, hospitals and any space where exhaust must never reach supply, specify separated sensible recovery (plate or heat pipe). Wheels are excellent for clean commercial air but not for contaminant isolation – this is a core part of the application-based selection discipline.

Frequently asked questions

Can a wheel be made zero-leak? No – the rotating seal always passes a little; purge minimises carryover but cannot guarantee isolation.

Does plate leakage matter? Only at the perimeter gasket; a well-built plate core keeps streams essentially separate.

Need help specifying the right air-to-air heat recovery for your project? Contact the QIYU engineering team – WhatsApp +86 157 5335 5505, or email kuns913@gmail.com.

Questions fréquemment posées

Questions fréquemment posées

How does a plate exchanger avoid cross-contamination?

Separate channels keep the two air streams physically divided by thin plates, so there is no mixing except tiny leakage through seals or defects.

When is leakage acceptable versus dangerous?

Small leakage is fine for clean indoor-to-indoor streams, but for lab, kitchen or toilet exhaust where contaminants are present, even small leakage is unacceptable and separated cores or run-around coils are required.