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Original message

Cyon



75.138.26.180

"Need Help Sizing Duct" , posted Tue 22 Jul 19:39user profileedit/delete messagepost reply


This is the first and last time I'll have to do this and I have no clue how. All I need is for these 2 forms to be filled out.



System 1 Form:

Constant Velocity Method

Please Size Duct Work Using Velocity Rate of:
Trunk @ 800, Branch @ 400, Return @ 600, Filter Grill @ 300FPM

Construction Data

Equip CFM 1200

| Duct ........ | CFM | Width | Length | FPM |
|A.) Unit
Supply
| B.) ......... | ___ |. (12") .| ______ | ___ |
| C.) ......... | ___ | _____ | ______ | ___ |
| D.) ......... | ___ | _____ | ______ | ___ |
| E.) ......... | ___ | _____ | ______ | ___ |
| F.) ......... | ___ | _____ | ______ | ___ |
| G.) ......... | ___ | _____ | ______ | ___ |
| H.) ......... | ___ | _____ | ______ | ___ |
| I.) .......... | ___ | _____ | ______ | ___ |
| J.) ........... | ___ | _____ | ______ | ___ |
All-Branches: | ___ | _____ | ______ | ___ |
Floor Reg: ... | ___ | _____ | ______ | ___ |
Return
K.) ............. | ___ | _____ | ______ | ___ |
Filter Gr .......| ___ | _____ | ______ | ___ |



System 2 Form:

Equal Friction Rate Method

Please Size Duct Work Using Equal Friction,
Ignore All Velocity Over Rides Except Filter Grill @ 300FPM

Construction Data

CFM ........................... (1500)
Avail Ext Pres Drop......... (.35)
Subtract;
Wet Coil ...................... (.09)
Filter Grill ..................... (.06)
Flr Register ................... (.03)
Heat Strip ..................... (.01)
Tot .............................. _____
Lgt Supply Run ............... _____
Plus Ret Run .................. _____
Tot Run ........................ _____
Conv to Friction Rate....... _____
| Duct ........ | CFM | Width | Length | FPM |
|A.) Unit
Supply
| B.) ......... | ___ |. (14") .| ______ | ___ |
| C.) ......... | ___ | _____ | ______ | ___ |
| D.) ......... | ___ | _____ | ______ | ___ |
| E.) ......... | ___ | _____ | ______ | ___ |
| F.) ......... | ___ | _____ | ______ | ___ |
| G.) ......... | ___ | _____ | ______ | ___ |
| H.) ......... | ___ | _____ | ______ | ___ |
| I.) .......... | ___ | _____ | ______ | ___ |
| J.) ........... | ___ | _____ | ______ | ___ |
All-Branches: | ___ | _____ | ______ | ___ |
Floor Reg: ... | ___ | _____ | ______ | ___ |
Return
K.) ............. | ___ | _____ | ______ | ___ |
L.) ............. | ___ | _____ | ______ | ___ |
M.) ............. | ___ | _____ | ______ | ___ |
N.) ............. | ___ | _____ | ______ | ___ |
O.) ............. | ___ | _____ | ______ | ___ |
Filter Gr ........| ___ | _____ | ______ | ___ |

 


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