Water flowing out of your water heater is alarming at best and highly destructive at worst. Knowing what to do can help minimize damages.
1. Don Safety Gear
Naturally, the water coming out of the hot water tank will be hot—usually around 120 F depending on your heater settings. It may be even hotter if the tank overheated. There may also be steam. It's best to put on heavy gloves, durable or waterproof footwear, and safety goggles if you need to walk through the flooding water or approach the heater in order to turn it off. Otherwise, you could suffer burns from the water or the steam.
2. Shut Off the Water
Shutting off the water will stop the fresh flow of water and stem the flood. The water shutoff valve is likely located on the side of the tank where the main water line enters the heater, but in some cases it may be mounted on the wall or floor next to the tank. Turn the valve to the right in order to shut off the flow of water.
3. Cut the Power
Next, turn off power to your water heater. You do not want an electrical short to occur, especially if you don't know the exact cause of the malfunction that lead to the tank bursting. Some water heaters have a control switch on the tank itself, making shutdown easy. Otherwise, you need to cut power at the breaker box. The circuit that controls the water heater should be clearly labeled in your breaker box. Often, the water heater is on its own circuit, but if it's not, you may have to cut power to the entire section of the house.
4. Contain the Flood
Now that the water flow and fire risks are under control, it's time to minimize flood damage. Surround the flood zone with rolled up towels to prevent it from expanding. Then, use towels or a string mop to soak up and remove the water. Act quickly, especially if your heater isn't directly on a concrete floor, so that you can minimize the chances of water damage. Use fans to circulate the air and dry the area more quickly so mold doesn't grow.
5. Get Help
Once the initial issues are under control, contact a plumber. They can replace your water heater so you won't be stuck taking cold showers for the foreseeable future. Usually a burst tank means you will need to install a new water heater.
If your water heater bursts after hours, contact an emergency plumbing service in your area.