Reducer in Blower Inlet

QUESTION
Why is the reducer in a blower inlet line eccentric with bottom side flat?

REPLIES

Gator
If the incoming air is moist a top flat or concentric reducer could result in a small pool of liquid collecting in the suction line (if the inlet piping comes from the top).

SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=377135
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