Sizing Refridgerated Air Dryer

If inlet conditions are different from rating conditions, dryer capacity will be affected as shown in the Dryer Sizing Chart. Inlet air temperature inlet pressure, ambient air temperature and air flow must be established before a dryer can be specified for your application.

Example: Select a dryer for 30 scfm air flow at 90 psig inlet air pressure, 150°F inlet air temperature, and 80°F ambient air temperature condition.

Step 1 On the Dryer Sizing Chart above, locate the inlet air temperature, 150°F.
Step 2 At 150°, read across the chart to 90 psig inlet air pressure. The correction factor is 1.08.
Step 3 To adjust the required flow for standard rating conditions, divide the required flow by 1.08.
30 scfm / 1.08 = 28 scfm
Step 4 Using the ratings and dimensional data, select a dryer that has a rated capacity of 28 scfm or larger.
Step 5 Dryer capacity is also affected if the ambient temperature is different from 95°F. For accurate dryer sizing, divide the adjusted dryer flow determined in Step 3 by the appropriate correction factor from the table. For 80°F ambient air temperature, the required dryer capacity is:
28 scfm / 1.22 = 23 scfm