[richard baechle]

For some reason I cant find what this is. Off the 1/2″ line on the top it looks like an A / V and I think it means alcohol vapor but I’m not sure. Any help is appreciated.

Discussion

[Mark Layport]

A/V = Atmospheric Vent

[Anton Dooley]

This can also mean Automatic Vent.

This, and other abbreviations, may have different meaning depending on the Client / project etc., so your first check, should be to look on the P&ID lead sheets.
These lead sheets should list all P&ID Symbology, abbreviations, codes, line number structures etc.

http://pipingdesigners.com/contents/tips-tools-training/section-1-glossary-terms-definitions/101-section-1a-piping-terms-glossary#top

[Anton Dooley]

.

[Ernest Rodriguez]

vent to atmos

[Author]

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