Thanks!. The capacity would be same but the cfm splits into OA (outside air) and RA (return air). For example: 2 ton unit @ rule of thumb 400cfm/ton we have a supply cfm of 800cfm. So if we need 30cfm of OA and the return is 770cfm. Hope this helps
I have a question related to this. Usually when you have OA ducts passing through fire rated walls, either a FSD or FD is required. Do they vary depending upon the ASHRAE picked for the calculation ?
Not really. Ventilation remains the same but we just want to make sure we provide FD in fire rates walls. The architect will provide with the life safety plan where it indicated which walls are 1 or 2hr rated walls.
@@hvaceasymath thanks for the response. The reason I’m asking is that I have seen both (fsd and fd) being used in nyc for OA systems in nyc. So I was just wondering which one should be used for them
@@viniciusbraga5846 FD, FSD and combination depends on the penetrations and fire wall rating provided in sections 717.5.1, through 717.5.7 and 717.6 of Chapter 7 of NYC Building Code 2022 (link: www.nyc.gov/assets/buildings/apps/pdf_viewer/viewer.html?file=2022BC_Chapter07_FireResistanceWBwm.pdf§ion=conscode_2022). Every state and city have different regulations. I hope this helps.
Thanks for your comment! I will make a video in the future about Zone Air distribution Effectiveness. This basically indicates how efficiently a system delivers air to the breathing zone. There are different configurations depending on the diffuser locations.
Gracias por el comentario. Es correcto lo que indica, pero además de los 15cfm debemos añadir OA debido a la superficie (área) lo cual es 0.06*146=8.76cfm. entonces (15cfm + 8.76cfm)/0.8 = 29.7cfm Thanks for the comment. it is correct but besides 15cfm we add OA due to area which is 0.06*146=8.76cfm. Then (15cfm + 8.76cfm)/0.8 = 29.7cfm.
Great video!
Thank you!
Great videos. I have a question. When we provide fresh air for fcu, does it effect to fcu capacity?
Thanks!. The capacity would be same but the cfm splits into OA (outside air) and RA (return air). For example: 2 ton unit @ rule of thumb 400cfm/ton we have a supply cfm of 800cfm. So if we need 30cfm of OA and the return is 770cfm. Hope this helps
@@hvaceasymath thanks you're advice
Well done @@hvaceasymath
@@imtiazshinwari4527thank you!
I have a question related to this. Usually when you have OA ducts passing through fire rated walls, either a FSD or FD is required. Do they vary depending upon the ASHRAE picked for the calculation ?
Not really. Ventilation remains the same but we just want to make sure we provide FD in fire rates walls. The architect will provide with the life safety plan where it indicated which walls are 1 or 2hr rated walls.
@@hvaceasymath thanks for the response. The reason I’m asking is that I have seen both (fsd and fd) being used in nyc for OA systems in nyc. So I was just wondering which one should be used for them
@@viniciusbraga5846 FD, FSD and combination depends on the penetrations and fire wall rating provided in sections 717.5.1, through 717.5.7 and 717.6 of Chapter 7 of NYC Building Code 2022 (link: www.nyc.gov/assets/buildings/apps/pdf_viewer/viewer.html?file=2022BC_Chapter07_FireResistanceWBwm.pdf§ion=conscode_2022). Every state and city have different regulations. I hope this helps.
Could you explain about Ez as well?
Thanks for your comment! I will make a video in the future about Zone Air distribution Effectiveness. This basically indicates how efficiently a system delivers air to the breathing zone. There are different configurations depending on the diffuser locations.
@@hvaceasymath Thank you so much for your kind responses.
¿Acaso esas 3 personas no están necesitando 15 cfm X 3 =45 cfm ?
Gracias por el comentario. Es correcto lo que indica, pero además de los 15cfm debemos añadir OA debido a la superficie (área) lo cual es 0.06*146=8.76cfm. entonces (15cfm + 8.76cfm)/0.8 = 29.7cfm
Thanks for the comment. it is correct but besides 15cfm we add OA due to area which is 0.06*146=8.76cfm. Then (15cfm + 8.76cfm)/0.8 = 29.7cfm.
Awesome
Thanks for your kind comment!
❤
Thank you!
Great video !
Thanks for your kind comment!