pf100 Supply duct sizing

[dmaclaren]

This is the information from the manual. If the opening out the pf100 is only 14x18, how can you get the min on the large motor?

Velocity 500fpm 700fpm 900fpm
1000 cfm. 270 in² 210 in² 160 in²
1450 cfm 360 in² 290 in² 220 in²
1638 cfm 470 in² 360 in² 290 in²

Am I missing something here? I know the unit I will be pickign up is the larger one and I can always set it on the lower setting. I am trying to find ducting that I can match the 14x18 into my main trunk of the existing forced hot air. Then from there, it will go through the existing duct.


Thoughts, ideas?

Thanks,
Don

 

[P0ZBURN]

I got hung up on the duct sizing as well. I just matched the largest size duct I had in my existing main trunk, with the discharge of the pf100. It works fine so far.

 

[exoilburner]

This is my duct section that adapts the PF100 duct size to my existing oil furnace main hot air supply duct size. Can you get a sheet metal shop to make this piece but have them modify the dimensions to fit the size of your existing sheet metal duct? Hope this helps. You should be able to print or save this image by itself by right clicking on it with your mouse.

 

[exoilburner]

Are you going to tell us how you solved this?