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info:howto:duct_sizing_rules_of_thumb

Duct Sizing Rules of Thumb

General rule would be that 1sq“ of filtered return will move 2 cfm.

Figure unit tonnages at 450-CFM per-ton of cooling.

Therefore our 2 1/2 ton unit upstairs needs 1125 CFM of air movement.

A ton of refrigeration (12,000 BTUs per ton) is the amount of heat required to melt a ton (2000 lbs.) of ice at 32 degrees Fahrenheit.

info/howto/duct_sizing_rules_of_thumb.txt · Last modified: 2009/09/09 11:43 by tomgee