I'm designing a grocery store. I have reviewed chapter 5 of the 50% AEDG for grocery stores and found that I can use the SZVAV DX with DOAS (HV6). The guide states that I should meet or exceed the efficiency levels in table 5-16. I have a 26 ton RTU (312 Mbh) which is large than the highest listed with an efficiency 240 Mbh. The table just says "not recommended" if >240 Mbh. In the Climate zone 4 recommendation for my SZVAV DX Package RTU with DOAS there is also a maximum external static pressure listed a 0.7 in w.g.
Will this large (312 Mbh) system be acceptable for the prerequisite? Will I be able to get any additional points in Eac2 if I don't reduce the size and provide two separate systems under the 20 ton (240 Mbh) size limit? With the larger RTU I also have designed 1.0 in w.g., is this and issue? The not recommended is ambiguous
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
December 27, 2017 - 1:14 pm
All of the items in the tables of these guides are recommendations for acheiving the 50% savings. LEED requires that you meet every one of the items within these tables to demonstrate credit compliance. So "not recommended" means it is not allowed. Both of the issues you raise means that you would not be in compliance and can't meet the requirements for the HVAC related points.
Richard Hawkinson
Mechanical DesignerHarris Group
December 31, 2017 - 12:44 am
This would mean that I could still comply with the 50% savings just not get any points toward the HVAC related right? It doesn't mean I don't comply with a prerequisite? I've always done energy modeling in the past and don't want a surprise late in the project.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
January 2, 2018 - 1:10 pm
I was thinking LEED BD+C 2009 when I replied before, sorry for the confusion. The AEDGs are not an option to demonstrate prerequisite compliance in CI-v4. if you are not doing an energy model then the other option is 90.1 compliance with the mandatory provisions and some reductions in energy use for lighting and plug loads.