We are designing a retail strip center. Due to the size, the baseline system is VAV w/ reheat. The proposed design is using CV RTUs. Currently, the model is setup with 2 baseline systems, one for all of the retail spaces and one for a restaurant tenant. There are 14 CV RTUs designed for the proposed model. Do we need to change the baseline to match the 14 systems of the proposed design? Does the baseline restaurant system need to be a different system type than the baseline retail system? If the restaurant doesn't have to be different that would be ideal, as it is already been modeled.
The restaurant is approx. 4,000sf and the retail areas are approx 62,000 sf.
Thanks
Christopher Schaffner
CEO & FounderThe Green Engineer
LEEDuser Expert
963 thumbs up
March 25, 2011 - 3:59 pm
By ASHRAE 90.1-2007, your baseline system should be System #5 - Packaged VAV with reheat.
Because the restaurant is only 4000 sf, it doesn't qualify for one of the exceptions in G3.1.1, so the Baseline Case should be modeled as a single system type.
According to G3.1.1, for System 5 "each floor shall be modeled with a separate HVAC system." So your number of systems in the Baseline Case depends on how many floors you have.
Joel Kerschen
19 thumbs up
March 25, 2011 - 5:15 pm
Thanks for the quick response. When you say "single system type" does that mean a CV system like system #3 in 90.1 or just another system 5?
The whole complex is only single story. So i'm guessing my assumption for 2 systems (one restaurant and one retail) is correct?
Christopher Schaffner
CEO & FounderThe Green Engineer
LEEDuser Expert
963 thumbs up
March 25, 2011 - 5:40 pm
No. If it is a single story, than the Baseline Case is modeled as one system - System #5
Joel Kerschen
19 thumbs up
March 25, 2011 - 6:12 pm
I have a somewhat unrelated question. Would parasitic losses from an energy recovery wheel be considered a process load?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
March 27, 2011 - 1:05 pm
Does not sound like a process load. If it is a part of the energy recovery unit the parasitic load would be a part of the HVAC energy use, which is regulated.