All,

I'm starting a new model in Colorado with an elevation of 5,000 ft that has an air-cooled chiller plant. When running selections to determine the performance of the chiller I'm noticing that the performance of the chiller is worse due to the density of the air, which makes sense as more fan power is needed to reject the heat.

When I run a chiller only eQUEST model and change the elevation from 0 to 5,000ft, there is no change so I don't believe eQUEST accounts for air density at the plant level like it does on the system level.

So my question is, how do I derate my baseline DX system performance to account for the altitude difference? If I plug in 90.1 values into the baseline and actual selection values, I'm unfairly improving the baseline. I believe AHRI tests everything at sea level.

Thoughts?