Crazy High Unmet Heating Hours on ASHRAE 90.1 Baseline Model

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Good afternoon everyone!

I am working through the process of creating an ASHRAE 90.1-Appendix G baseline model and cannot understand where I've gone wrong in the design. I have done a number of energy audits using eQuest but have never been through the LEED process and thus this is my first attempt at dealing with 90.1 directly. Any help you may offer would be much appreciated and I am more than happy to compensate any time spent.

The building is a System Type 7 - VAV with Reheat - and my cooling hours are 0. However, I can't seem to get my VAV terminal units to provide enough heat at any time during the year. When I allow eQUEST to size the capacities on their own, not enough heat is added and temperatures throughout the winter and in all zones remain below 60F. But when I specify a Maximum Heating Rate at the Zone Terminal the addition rate doesn't change! I've tired increasing the throttling range, which had some effect. The only thing that had a significant effect on the unmet heating hours was increasing the Heating Design Temperature for each Zone. But this also had the effect of dramatically increasing the cooling unmet hours! Finally, and most confoundingly, my heating energy consumption in the winter is significant! Where is it all going?? I am at a total loss.

I hope I was clear in articulating my issue and again appreciate your assistance.

Dana M. Savage :: Mechanical Engineer
CONTACT :: DSavage at cfrengineering.com :: C: 301.717.0003
ADDRESS :: 20251 Century Blvd. Suite 120 :: Germantown, MD 20874
www.cfrengineering.com
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