Lansing Heating And Cooling

Why Does My Water Heater Make a Knocking Noise?

Water Heater Installation Lansing, MI

Does your home’s hot water heater make an eerie knocking or popping sound that could belong to the soundtrack of a horror movie? Don’t be alarmed. The fix is really quite simple. Just make sure you flush your hot water heateronce a year to get rid of any built up sediment on the bottom of the tank. Whether you do this on your own or hire a Lansing heating system contractor, giving your water heater proper maintenance will prevent expensive repairs in the future.

If it has been years since the last time you flushed your hot water heater, you will want to call a reputable heating and cooling contractor. Trying to flush that much sediment by yourself may result in water heater leaks.

What causes sediment buildup?

Over time, sediment will build up on the bottom of your water heater tank. When this happens, the high temperatures of the water heater cause the sediment to harden and trap pockets of water. Under high temperatures, the moisture turns into steam and bursts through the layer of sediment to create that disconcerting knocking noise from your water heater.

How do I flush my water heater?

To make sure water heater sediment doesn’t cause any issues with your heating system, you will need to drain the tank and flush it out annually. Luckily, the steps are simple enough for a beginner DIYer to follow.

You will need:

  • Thick protective gloves
  • Garden hose
  • Flathead screwdriver
  • 5-gallon bucket (optional)

1. Turn off fuel or electrical power.

Whenever you do repairs to your hot water heater, you will always need to shut off its power source. Depending on whether you have a gas or electric water heater, you will need to shut off the fuel or electrical power. Be sure to follow the manufacturer’s instructions.

2. Turn off cold water supply.

Near the top of your hot water heater should be two valves. One is responsible for feeding in cool water and the other for sending out heated water. The valve you want should be clearly marked blue for cold water supply. Turn the valve 90 degrees to shut it off.

For your safety, we recommend that you wait overnight (or at least 30 minutes) for the water in your tank to cool down. If not drained properly, the scalding hot water could cause personal injury.

3. Turn on hot water from nearby faucet.

While draining and flushing the tank, be sure to keep hot water running from a nearby faucet. Not only will this introduce air flow into your hot water heater to ease draining, but it will also prevent a vacuum from forming in your lines.

4. Attach garden hose to drain valve.

When doing this step, be sure that you are wearing your protective gloves. Also make sure that the other end of the garden house is placed in a safe area for the water to drain, such as a basement drain or bucket.

5. Drain water heater tank.

When you open the drain valve, dirty water will come out through the hose. Don’t be alarmed. This merely shows that the sediment is being cleared from your water heater tank. Keep going until all the water is drained from the tank.

The water coming out may be extremely hot, which is why it’s important to wear your protective gloves. If you are using a bucket to drain the water into, you may need to empty your bucket several times during this process.

6. Flush water heater tank.

When there is no more water coming out, you will need to make sure that there is no residual sediment left in the tank. Open and close the cold water supply valve a few times to disturb any residual sediment left on the bottom of the tank. Stop once the water comes out completely clear.

7. Close tank drain valve.

Once you are done flushing your hot water heater, disconnect the hose, and close the tank drain valve. Also, make sure you shut off the hot water faucet you turned on earlier.

8. Fill water heater tank.

Open the cold water supply valve to fill the water heater tank back up. To make sure there are no air bubbles in your lines, we recommend running all the hot water faucets in your home until normal water pressure returns.

9. Turn power back on.

Once the tank is completely filled, relight your water heater by following the manufacturer’s instructions. Congratulations, your hot water heater is set for another year!

If you don’t feel confident flushing your own water heater, you are encouraged to seek out the services of an experienced heating system contractor in your area. The licensed water heater installation contractor that comes out to your house will be able to flush your hot water heater so that you don’t have to worry about sediment buildups for another year.

If you are interested in our residential hot water heater repair service, please feel free to give our Lansing heating system contractors a call at (517) 485-9437. The water heater repair contractors at Block Sloane Heating & Cooling work hard to help homeowners prolong the lives of their home heating systems.