How the Air Moves
In a counterflow core the two airstreams run in opposite directions; in a crossflow core they cross at right angles. Counterflow lets the cold outgoing air meet the coldest part of the incoming stream, squeezing out more energy.
Effectiveness Difference
- Crossflow plate: typically 60 to 65 percent sensible
- Counterflow plate: typically 70 to 75 percent sensible
Trade-offs
| Crossflow | Counterflow | |
|---|---|---|
| Effectiveness | Good | Better |
| Manufacturing | Simpler, cheaper | More complex |
| Pressure drop | Lower at equal size | Slightly higher |
Which to Specify
Crossflow fits most commercial ventilation where space and cost matter. Counterflow is the choice when every point of effectiveness counts, such as in passive-house or low-temperature heating systems.