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sachinm08
27-04-2009, 07:04 AM
The tonnage of ductable ac is 20.8 ton.

Cfm of machine : 8000 cfm
external static pressure :417 pascal / 1.67 wg
total ducting length : 123 ft ( 37.5 mt )

will this capacity ductable machine effectively throw air upto this ducting length.

icecube51
27-04-2009, 07:10 PM
i think you soult refrase your question better. wat brand is the duct-type? the given lenght (37.5mtr) is the overal handeling or the given specifics from the manufacturer?

ice

Brian_UK
27-04-2009, 10:46 PM
What size is the ductwork?

123ft of 4" circular duct
or
123ft of 6ft circular duct?

dougheret0
29-04-2009, 06:56 PM
Both Icecube51 and Brian K are trying to tell you that the capacity of any duct is a function primarily of its diameter. The May issue of the ASHRAE journal will have an article explaining simple equal friction duct sizing and includes an excel spreadsheet that can be downloaded to perform duct calculations.

icecube51
02-05-2009, 10:58 AM
an if you Google,you can find enough progs with calculation possibillitys to point you in the wright direction.

Ice