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Multiplying Capacities? when using Multipliers

My question : I am working on a midrise residential tower. I added multipliers on the thermal tab. I also multiplied the capacities for my Heating, Cooling, and Airflow rates. When I check my proposed model outputs compared to the baseline outputs, I can see that the energy consumption (on cooling) for proposed is several times higher than what is shown on the baseline model. I am thinking it has to do with the capacities being multiplied. I multiplied the capacities due to what I read on the "tips and tricks for energy plus document" [page19-20]. I thought that is what it said to do, but I might have misinterpreted what it said. Any insight on this would be much appreciated.

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Thanks,

Fabian

thenewFabian's avatar
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thenewFabian
asked 2019-04-26 13:52:49 -0500
__AmirRoth__'s avatar
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__AmirRoth__
updated 2019-06-05 11:57:50 -0500
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Upsizing the HVAC system to meet the multiplied load is the correct approach. I would suggest using autosize for all autosized inputs and comparing the results with your inputs. You might also try eliminating the height variation as discussed in tips and tricks if you are modeling height variation. Your proposed model does not use multipliers?

rraustad's avatar
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rraustad
answered 2019-04-26 15:28:09 -0500
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Thank you for responding. I just switched all my inputs to auto size. I now see that my cooling output is higher. so that makes me think that its not the increased capacity inputs. I did not include the height variations. I modeled them on top of each other with adiabatic surface adjacencies. I did add the multiplier count on the thermal tab. But now I am thinking the increased capacity might not be the issue. So I am thinking I am supposed to multiply the capacity inputs for Cooling, Heating, and airflow as well as add the multiplier count. Thanks

thenewFabian's avatar thenewFabian (2019-04-26 15:46:44 -0500) edit
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