Heat-pipe exchangers use a row of sealed tubes charged with a working fluid that evaporates on the warm side and condenses on the cold side. Plate exchangers use stacked thin plates. Both are sensible-only, but their failure modes differ.
Comparison
| Heat pipe | Plate | |
|---|---|---|
| Moving parts | None | None |
| Frost handling | Self-drains; less bridging | Needs bypass / preheat |
| Cross-contamination | None | None |
| Effectiveness | 60-75% | 80-90% |
| Orientation | Must be vertical | Any |
| First cost | Higher | Lower |
When heat pipes win
Heat pipes excel where frost is severe: condensate drains by gravity and the device tolerates partial icing better than a plate. They also need no specific orientation of the airstream paths.
When plates win
Plates deliver higher effectiveness at lower cost and suit most temperate duties where frost control is handled by a winter bypass.