I like how the low point drains are shown to be...... wait for it..... NOT the low point in the system.
I can't tell where the "city water fill" ends in that diagram.... maybe just hard to see at the reduced size.... Am I correct to assume it just tees into a cold water line to pressurize it. I assume there is a check someplace not shown so that when not connected to city water, the pump doesn't pump water out the inlet....
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