I cannot shut the hot water valve in bathroom sink and I need to replace the washer it is dripping. Do I have to shut the main?

If you can't turn off the angle stop then, close the Cold Water shut off to the HW heater, open a faucet and it should not run. To be real safe turn off the main gate valve where water comes into the house or, if allowed, turn it off at the water meter.

If it is Deck Mounted Faucet than you should have hot and cold angles stop (valves) under the sink, inside the cabinet. You close them and you can work on your faucet w/o shutting off main water valve. If it is a Wall Hung faucet than you have to shut off main water valve for whole house.

Milo

Hi Rbonelli

If the faucet has two handles, you can either shut off the water main, or, if you have a water heater or tankless water heating unit, you can shut off the cold water shut off valve into them and that will shut off the hot water ONLY. If it is a single handle faucet, shut off the water main!

Mark

Wow guys, we all posted at the same time! Slow day for all??