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- May 4, 2025
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- Monterey Bay area, California
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Air purge, typically!BTW what is the red button on the lid?
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Air is trapped at the top of the housing after initial water pressurization, and after any service… that will be the highest point in the housing; pressing the button opens a valve at the high point to release trapped air bubbles!
— after introducing air to the plumbing: you’ll usually get a hiss of air, then a bit of water/air mixed, then just water as you hold the red button down… once it’s releasing water only, you’ve purged all the air out of the housing!

Probably not useful in this application?