I've only seen one water heater with the vaccum relief valve and am just ignorant about it's use or why it is there.... would someone just explain it to me....or direct me to a good reference. I've seen some in strange places on institutional plumbing and never understood why they were in the plumbing. I assume they are to stop the water from siphoning out of the water heater if the incoming cold water line were opened. I'm kind of trying to understand why it comes after rather than before the expansion tank.
Thanks Steve for posting the picture!
Thanks Steve for posting the picture!
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