Hi everyone!
If exhaust fans serving unconditioned spaces are considered as a process loads (e.g. parking garage exhaust fans) and should be modeled as in proposed case, it means that it should be modeled with exactly the same eff., PD and Pfan? Or these fans are also regulated and it is necessary to follow Table 10.8 of Standard? In that case I presume the calculation of Pfan depends on wheter the fan is CAV or VAV and also if residential or non-res... So if I have office buidling and the fans in question are CAV I should use bhp equation for "Systems 3-4".
Is that assumption correct?
Thank you very much!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
September 9, 2016 - 10:22 am
Yes they should be modeled identically. Just the fan motors are regulated, not their use in that application like the HVAC system fans. You can claim credit for using premium efficiency motors in this application as an exceptional calculation.
Yes in your proposed model use the BHP of the fans in accordance with the design.
Samuel Sura
MrSALVIS
3 thumbs up
September 9, 2016 - 12:40 pm
Thank you Marcus. Now I see what you mean, but we are outside the U.S. It means that our garage fan motors do not follow Standard efficiency requirements according to Table 10.8. We have designed fan motors according to Eurovent standards and that's the point what confuses me, because our fan motor design is little more efficient as it is required by Table 10.8. I still don't get it if in this case the Baseline garage fan motors should be as designed in proposed or should follow minimum nominal full-load efficiency listed in Table 10.8? So the Pfan will be different of course.
Thanks!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
September 9, 2016 - 1:28 pm
So if you do an exceptional calculation you can claim credit for motor efficiency in a process load. The baseline is according to Table 10.8, the proposed as designed.
If you don't do an exceptional calculation then model the baseline identical to the proposed design.
Samuel Sura
MrSALVIS
3 thumbs up
September 13, 2016 - 6:24 am
I appreciate your help Marcus! Thank you.