How to Drain a Gas Hot Water Tank
- 1). Turn off the gas supply to the hot water heater. Some appliances have a switch used to turn off both the pilot light and gas supply. Other units have a valve on the supply line that needs to be turned to the off position with a pair of pliers.
- 2). Stop cold water from entering the hot water heater tank by turning the valve off.
- 3). Bleed off pressure in the system by opening a hot water tap in the closest bathroom. Leave the tap open.
- 4). Attach a garden hose to the drain valve at the bottom of the hot water heater tank. Run the other end of the hose outside the home.
- 5). Open the tank's drain valve fully. Open the pressure-relief valve at the top of the tank. This helps create additional pressure to drain the tank. Allow the water to completely drain from the tank.
- 6). Close the drain valve, remove the garden hose, shut off the hot water tap in the bathroom and close the pressure-relief valve atop the water heater tank. Open the cold water in-feed valve and let the tank fill completely with water before turning the gas supply line back on and re-igniting the pilot light.
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