Hello everyone.

The subject and the following question might be pretty basic, but since I have no prior experience with LEED certification I thought it would be best to hear what more experienced people have to say on this matter.

We are currently working on a multi-storied commercial building located in Dhaka, Bangladesh. The building in question is targeting LEED platinum certification, and has achieved the precertification for the same.

At this moment, we are in the middle of selecting the chillers. There are 4 chillers in the plant, each having a cooling capacity of 600TR. The MEP consultant firm has specified a COP of 6.8 for the chillers, and the same datasheet has been shared for the precertification and energy simulation. However, during the chiller selection process we are getting 2 sets of selection and performance data from the suppliers, one is the performance data at AHRI design conditions and the other is for the design data specified in the consultant's datasheet.

For example, we have received the selection sheet of a centrifugal chiller under AHRI conditions (Evp. leaving temp: 6.2 degree celsius, Evp. entering temp: 12.2 degree celsius) which meets the COP requirement. The same chiller's selection sheet, when considered under the actual design conditions ((Evp. leaving temp: 7 degree celsius, Evp. entering temp: 14 degree celsius), the COP is less than 6.8.

This is where I am stumped, as I am not getting a clear picture from the suppliers as well as the local LEED consultants. So my questions are-

1) Does LEED look at the AHRI standard condition data or the actual design condition data when calculating the COP?

2) As we've been told by the local LEED consultants, minimum COP of 6.2 is required for platinum certification. If we select a chiller with a COP lower than 6.8 but higher than 6.2, how would that affect the overall awarded points? For reference, the building has been awarded 82 points in the precertification.

Once again, having no experience in this field, I might have missed some crucial information in my post that's required for answering the question correctly. If you feel some other information is required, let me know and I will share them with you.

Thanks to everyone in advance.

Regards,

Shuvajit