Center Zones Too Warm

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Hey all,

Working with OpenStudio and when looking at the zone temperatures, the center zones are getting significantly warmer than my exterior zones. It may also be important to note that while this is the case year round, in the summer months the affects are much more noticeable. I am asking for some troubleshooting techniques around this kind of occurrence.

The one thing that may be strongly affecting this is that the center zones aren't serve by any of the AHUs, they only have exhaust fans in the rooms because they are washrooms, copy rooms, etc. But the exterior zones stay within the setpoints that I have set pretty well. It may have to do with air changes per hour and air flow between zones. Just wondering if anyone can offer any advice on this matter.

Thanks in advance for the tips guys.

Edit: This may help in determining the problem. Below is a screenshot of a center and exterior zone's air temperature.

My building loads and occupancy begin at 7:00 which is where I expected a jump in temperature to be. That being said the 2C zone temperature jumping from 22.15 to 41.83 is a bit unreasonable. I do think David's suggestion of zone mixing may help fix this but I am unsure of how to do that.

I may also be using the space infiltration design flow rates and schedules for those incorrectly. I say this because the AHUs run from 07:00 to 21:00. But much of the occupancy and loads in the building are complete at 16:00. The next screenshot shows around the times I am concerned with. Basically I see the drop in 2C air temperature at 16:15 which is expected but the temperature stays fairly constant until the AHU unit shuts off at 21:00. For the space infiltration I just used one of the predefined wholeBuilding md office loads based on the flow/exterior area for the exterior zones and used ACH for the center zones. The schedule applied to these loads was a medium office infiltration quarter on but adjusted to being "on" from 07:00 to 21:00.