Plumbing question of the day: replacing a shutoff valve

[artie67]

Where is the shut off valve? Under a sink? Plumbers call those "angle stops". Lingo for the store helps. Always take them or it to the store to match.
Turn off the valve at the heater and then open the valves downstairs. A bucket under the valve for replacement is always a good idea. I always take out the screen from the faucet for a day or so due to the breaking loose of the rust and lime in the pipes after doing repairs.