- 1). Turn off the electricity for the hot water tank. Go to the main circuit breaker in the house and look for the switch that controls the hot water heater, which should be labeled. Move this switch to the "Off" position.
- 2). Turn off the gas supply, if this is a gas water heater. Look for a ball valve connected to the end of the flexible tubing connecting the water heater to the gas supply pipe. Rotate the gas valve to the "Off" position.
- 3). Allow the water in the system to cool for approximately an hour.
- 4). Identify the hot water expansion tank. These are typically installed above the cold water supply line. They are shaped similarly to propane gas cylinders.
- 5). Turn off the cold water supply valve located near the expansion tank. Rotate the knob to the right to cut the water.
- 6). Look for the drain or combination valve on the expansion tank. Hold a bucket or other similar container underneath this valve. Open the valve with an adjustable wrench and allow the contents of the tank to drain into the bucket.
- 7). Loosen the coupling connecting the expansion tank to the cold water supply line with an adjustable wrench. Some water may drip out, which is normal.
- 8). Loosen the retaining straps or nuts holding the expansion tank in place. Lift it up and off the water supply coupling and set aside.
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