How to Drain a Water Heater
Water heaters are something most homeowners never think about, until there's a leak or the hot water stops flowing. Most water heater manufacturers recommend draining the water heater tank every 6 or 12 months. Flushing the tank helps to remove sediment that can accumulate over time at the bottom of the tank. The sediment is mostly made up of minerals and other particles. If your home has hard water, sediment is likely to accumulate faster.
As the sediment builds up it creates an insulating layer between the burner at the bottom of the tank and the water. The burner has to run longer to heat the water, reducing the water heater's efficiency and shortening its lifespan. Flushing the water heater tank regularly will remove the sediment before it can significantly reduce the the efficiency of the burner.
Flushing a water heater is straightforward process, but you should always consult with the owner's manual for details on your particular make and model. It's also a good idea to know where your home's main water shut-off valve is located, should there be a problem during the process.
1. Before working on the water heater turn off the gas to the OFF position. If it's an electric water heater, turn off the electrical supply to the unit at the circuit breaker by switching the circuit to the OFF position. Allow the water to cool down for a couple of hours. If the tank is not cooled down ahead of time, wear insulated rubber gloves to prevent scalding.
2. Turn the water supply valve off. The supply valve is located at the top of the water heater.
3. Securely attach a garden hose to the drain valve at the bottom of the tank. Place the other end of the hose outside the home below the level of the drain. Or, place the hose in a large (at least 5 gallons) bucket and turn off the valve each time the bucket fills up.
4. Open the drain valve knob or lever. In some cases a screw driver will be needed to turn the knob to open the drain valve.
5. Carefully pull up on the pressure relief valve, located near the top of the tank, to open it. Jus loosen the valve enough to allow air to pass through.
6. Allow the water to drain completely. It can take up to 30 minutes for your water heater to completely drain.
7. Open the water supply valve at the top of the tank to flush out the water heater. Run the water for at least 5 minutes to flush out sediment. If you're using a bucket the water should look clean.
8. Turn the valve to fully close the drain where the hose is connected. Next, close the pressure relief valve on the water heater. Tighten the nut on top if you loosened it.
9. Disconnect the hose.
10. For a gas water heater, turn the pilot light to the ON position. Relight the pilot light if necessary by turning the valve to the PILOT position and using the ignitor switch on the valve, or a long lighter if it isn’t equipped with an igniter.
For an electric water heater, turn the power in at the breaker by switching the circuit to the ON position.
Have questions about maintaining your water heater? Call Grand Lake Plumbing and Heating. We're here to help.