HVAC load calculation problem

Hi guys, I’m currently doing a load calculation but I got some problem with the result.

I divided the floor into different thermal zone like below.
The HVAC result shows the G zone on the 3rd floor got a very high cooling load, it can be very abnormal cause the zone does not have any external window at all. And the cooling load result of G zone on the 3rd floor is much larger than the result of G zone on the 2nd floor.

Similar problem also exist in zone H.

I guess there are some of mistake in the model but I cannot find any. Could any one kindly help with this? Many thanks.

rhino.3dmbak (305.6 KB) gh.gh (757.6 KB)

I’ve uploaded the model file and the GH file.

@Darvey ,

This is a large GH definition and you really should upload a small sample needed to recreate your issue. But your geometry is clean and, just looking at your model, I see that your interior floors are not well insulated. I can also see that they also have no thermal mass:

So my guess is that the zone above G on the first floor has the sun basting through it’s windows onto the floor and much of this heat quickly conducts through this no-mass floor to zone G. I’m sure that adding some mass to this floor will probably dampen the peak. Or you could boot up the R-value a little.

@chris Hi Chris, thank you for your timely help. I’ve solved the problem, the sequence of the thermal zone is not as same as the sequence of the zone names, so the high load is actually not from the zone G. That makes the result becomes more reasonable.

In addition, I’ve tried to change the mass of the floor construction materials, and the load result reduced effectively.

Thank you very much.

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