The following graphs represent the increase in airflow resistance, relative to increases in the airflow volume, at standard temperature and pressure:

Whilst every effort is made to be accurate, Garfield Richards Engineering Co cannot accept responsibility for calculations based on these graphs. Further clarification should be sought.

Please contact us for further assistance.


  1. Typical Heat Exchanger Specifications and Descriptions
  2. Technical Data for 'T' and 'R' Models
  3. Technical Data for 'TF' Model
  4. Airflow Resistance Graphs

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