[stomachmonkey]

To be fair there is a lot I don't know but the basics of how things that you own should work is not too much to ask.

I'm at SIL's, having T-Day here. 10 people in the house.

Water heater just took a dump so it's all hands on deck and a mad scramble to keep basement from flooding.

My BIL turns off the main supply to the house, not a bad idea and the thing most people would do.

I run down to the basement and he has not shut off the the lines at the tank. I can hear the tank back feeding so I shut it down.

I try to explain to him how it works and he shrugs, "yeah but I shut off all the water". I tell him he did not need to do that, turn the main back on, "nah".

K, fine by me. I'm sure that'll work for you right up until your wife or MIL realize they have to go take a dump in the woods because they can't flush.

Good luck with that.