Question-and-Answer Resource for the Building Energy Modeling Community
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Similar experience like Ben. For smaller DX units it's really hard to get the "curve" or "performance table". But generally, it's not hard to get the rated condition efficiencies and its power draws on compressor, condenser fan, and evaporator fan. I always model those components separately and adjust compressor only COP based on rated data, not the ASHRAE 90.1 equation. Then I would be using the software default curve based on its sizing category. The tool would then adjust it from rated to design conditions.
For HPs, it's a lot easier to get a "performance table" which will show the relationship between OA(or EWT for WSHPs) vs TC vs Power Draw. I then manually create curves without the fan because I will be modeling them separately. Note the curve would reflect compressor only because fans are out.
Note I pretty much never use the efficiency adjustment equation for my proposed design unless I really can't find power draws. I use it for the baseline, if there is one.
