Hvac ductwork calculation (1 Viewer)

[pillguy]

Hey guys,
Replacing my 2.5 ton hvac system and need to verify ductwork is sized appropriate. I am seeing 200 square inches per ton as a rule. Can anyone provide insight and confirm?
Internet answers are all over the place.

 

[elliott10]

Which are you trying to size? Return or Supply?

 

[micruz60]

Check your local jurisdiction for code recommends and requirements.
Google ASHRAE for too much information.
hth