How to Shut Off a Sink's Hot Water Valve
- 1). Locate the valves under the sink. The hot water valve usually is located on the left.
- 2). Turn off the hot water line. Typically, turning clockwise will shut off the valve. If you are not sure which line is for the hot water, turn on the hot water at the faucet and then turn off one valve at a time until the hot water supply has been identified.
- 3). Locate your hot water heater if there are no valves under the sink. Turn off the hot water valve. Turning the hot water valve from here will turn the hot water off for the whole system.
- 4). Turn off the water, if necessary. Locate mainline water shutoff valve either outside or in the basement, and turn off the valve. This will turn off all water for the whole system.
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