Hi Everyone,
This questions is about unmet heating hours in a model. I've scoured the bldg-sim list but I haven't come across anything like the problem I'm having. I'm modeling a high school in New England. The unmet heating hours are 99.99%. I've checked the heating and cooling schedules, fan schedules, etc., adjusted the throttling range, and so on. The SS-O reports show that the majority of space temperatures are below 60F. The building is in New England, but I find it unlikely that during the majority of the summer the temperature will be below 60F in the building. It's not really a sizing issue either as changing equipment sizes does not do anything and the loads (for the most part) do not exceed the equipment capacity. Any help would be greatly appreciated.
Thanks,
Netty
Netty Nina
Netty,
One major problem that jumps out is that you have not fully defined your zone geometry in your building shells. I would start by going back to the Wizard and defining/redefining your shells and zones. (You do not want any yellow area left when you are finishing defining zones for a shell. Everything should be green.) Then, when defining systems, keep the eQUEST defaults as much as possible to get your model running properly before you change things. Make sure the model runs well before spending a lot of time doing custom windows in the Wizard, because the work will be undone if you have to make more changes to the shell/zone definitions.
Regards,
Bill
[Senior Energy Engineer 28Jun2012]
You just need to activate the coils, eg
Shaun
Shaun Martin LEED AP
Netty,
In addition to what others have suggested, take a look at your thermostats at the zone level of your HVAC equipment tab. I noticed that several (maybe all) of the defined systems are VAV. I looked at a few of the thermostats, and they were defined as proportional.
I encountered a similar problem in a different century when I was using VisualDOE and the fix was to change the thermostats to reverse acting. If you define them as proportional, the VAV boxes will close to the minimum position and continue to overcool the zone. If they are defined as reverse acting, the VAV boxes will begin to bring on reheat and open the damper when they have reached the min. CFM setting to maintain the thermostat setpoint.
I hope this helps you.
My best,
Mike Busman
Michael R. Busman, CEM