Piping and Instrumentation Diagram (Question)

AI Thread Summary
The discussion centers on clarifying the meaning of "air flow1/air flow2" in a piping and instrumentation diagram related to energy modeling. Participants suggest that it likely refers to minimum and maximum airflow values. Color coding in the diagram is also explained, with orange indicating return air, green for outdoor air supply, blue for primary air, and pink for exhaust air. One user requests a close-up of the diagram for better clarity, while others agree with the initial interpretation of the airflow labels. Overall, the conversation emphasizes the importance of understanding labeling conventions in instrumentation diagrams.
redux
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Hey everyone,

I am an energy modeling engineer, and I would like to ask a question regarding a project I am working on.

In the attached instrumentation diagram (and I also found this on AHU specification tables), what does it mean to have "air flow1/air flow2" (see figure). I deduce it is the "min airflow value/max airflow value", but I would like to be sure about this. Concerning colors, orange is return air, green is outdoor/fresh air supply, blue is primary air and pink is exhaust air.

Thank you all in advance for your time.

242027
 
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Welcome to PF.

That's a good guestion, but I am unable to zoom that image big enough to read what you are saying. Can you add a post with a close-up of the part of the image showing the label in question?
 
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Thank you, and thank you again for the fast repply.

242028
 
Thank you. min/max would be my guess also. Wait a while for others to weigh in also.
Label conventions sometimes seem irrational unless you know the underlying thoughts.
 
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redux said:
In the attached instrumentation diagram (and I also found this on AHU specification tables), what does it mean to have "air flow1/air flow2" (see figure). I deduce it is the "min airflow value/max airflow value", but I would like to be sure about this.
That's what it looks like, yes; it's probably reduced outdoor air and exhaust when the washer is off.
 
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Thank you all for the help.
 
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