Greetings,
The project we are modeling is an office building Core and Shell type with a Г shape. It consists of large office zones, as they will be later subdivided to the future tenants.
As the thermal zone requires, we are splitting these large zones, so that they to correspond to the thermal zone requirement. There are 5 office floor levels. They are served by three AHU. The AHUs however is serving every floor in a different way, meaning that they covers zones which do not coincide to the thermal zone split, which leads to additional splitting of the thermal zones, resulting in more and more rooms.
The questions is:
Could we combine the three AHUs, meaning sum-up their airflow quantities, fan powers, heat recovery parameters and to model these office floors as they are served by one large AHU. This practically will allow us to remain only by the floor splitting, which will be in accordance to the thermal zone rules.
You opinion is highly appreciated.
Thanks.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 17, 2018 - 10:04 am
In general it is usually best to model the project as designed. Deviations from that require you to provide a thorough explanation and justification to the reviewer. It often opens up the review to many questions. You will need to follow the rules governing thermal blocks in Table G3.1-7 and 8. If you can demonstrate that you meet the exception you can deviate from the design in the model. You will need to make the case to the reviewer that what you are doing is thermodynamically similar or is a conservative approach.