What to Measure
On site you need supply and exhaust airflow, and dry-bulb (and wet-bulb for enthalpy) temperatures on both sides.
Procedure
- Balance and confirm airflow with a hood or pitot
- Log inlet and outlet temperatures on both streams for a stable period
- Record pressure drop across the core
Compute Effectiveness
Use the measured temperatures in the effectiveness formula. For enthalpy wheels include humidity.
Judge the Result
Compare the measured value with the rated curve at the same conditions. A large gap means fouling, leakage, or a wrong selection. Keep the sheet as the commissioning baseline.