I'm replacing a toilet supply line valve.
Toilet is on lowest level of house, and supply line valve is literally the lowest valve in the house and supply line is literally the lowest water line in the house.
I plan to turn off the main shut off, and open cold water valves up on third floor (the upper level) and the cold water valve in that same lowest level bathroom's sink.
Then I plan to open the toilet supply line valve and drain that line into a low flat pan before removing and replacing the old valve.
Is there anything obvious (or maybe more importantly, not so obvious) that I'm missing regarding draining that line?
I *think* I've got the drainage issues / air issues / vacuum issues covered, but I'd rather avoid draining 10 gallons of water into a pan that holds maybe 2 gallons.
I'll have the wet dry shop vac and a bunch of towels handy in any event.
Thanks for your comments.