Hustlin' Hank wrote:
....
Air in water lines that are on city water can be a common occurence,
especially if you are at the end of the main line. When the pumps
loose power due to an electrical outage, or other reason, air is
produced thru what is called "cavitation" in the pumps volute. If this
is the case, there is not much you can due about it, other than
contacting your water company and see if they can (or are willing) to
either reduce the pressure slightly or take other measures. They way
want to know about your problem in order to maximize their delivery
and avoid other problems. Anyway, check with them before you call a
plumber.

What a bunch of mostly hooey...

And, even if it were, air in supply lines would show up in both hot
_AND_COLD_, not hot only...

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