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Flushing your water heater should feature prominently in your home maintenance to-do list.
Given the many hot water uses around a home, dealing with a broken heater is something you have to avoid at all costs.
Regularly flushing out the heater helps to get rid of mineral deposits and gunk that settle inside the heater.
Below are steps on how to flush a hot water heater.
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Steps on How to Flush a Hot Water Heater
1. Turn your water heater off
A part of knowing how to flush a hot water heater is understanding what needs to be done before the process starts.
If yours is an electric water heater, go to the power switch and switch it off. For a gas-powered heater, go to the thermostat located close to the bottom of the tank and completely turn it off or set it on pilot mode.
You may also need to switch off the gas in your gas-powered heater.
Leaving the power on when the water heater tank is empty can damage it. This step is also for your safety, and you do not want to touch the heater when there is still power running through it.
Before you start the flushing process, you may consider washing the dishes, taking a shower, and laundry because it will be a while before you can have hot water in your pipes again.
2. Turn off the cold-water valve.
The cold water from the inlet valve comes to replace the hot one escaping on the other side of the heating system. Without more water entering the tank, you can drain all the water in the heater.
Skipping this step will mean that you have a lot of water going down the drain, which can significantly increase your water bill.
3. Allow the water to cool off.
You can skip this step, but it is wise to wait an hour or two after turning off the cold-water valve to allow the water to cool off. This step is important if you plan to drain the water in your garden.
You also don’t want to handle scathing hot water at any point during the flushing process.
4. Turn on the hot water tap in the tub or sink.
The hot water taps should remain open throughout the flushing process. This prevents the formation of a vacuum in the lines when you are draining the tank.
5. Open Pressure Relief Valve
You can also opt to skip this step, but the water will drain faster when the pressure relief valve is open. It is also a way to test how well the valve is working so you will be killing two birds.
When opening the pressure relief valve, have a bucket or any large container below the drainage pipe to hold any water that comes out.
You have to be careful since the water coming out may be too hot, especially if you didn’t allow some time for the water inside the tank to cool off.
If no water comes out after opening the pressure relief valve, it is clear that the valve is broken. Consider replacing it as you flush your water heater.
6. Connect a hose to the outlet valve
Connect a garden hose to Spigot and turn it on. However, before you do so, ensure that the hose leads to a bucket or an open area outside.
If you did not allow the water to cool, make sure that the bucket is heat-proof. You also need to ensure that the hose is far from the entrance or any area that may get damaged.
If the water heater is fitted in the basement, you should consider getting a pump to bring the water up to the ground level.
Leave the hose to drain the tank until there are no sediment traces. If there were loads of sediments in the tank, you might have to drain the tank completely.
At first, the water coming out of the tank will appear brownish and get clearer as most of the sediments come out with the water
7. Flush the heater
This step is completed by opening the cold-water valve leading to the tank and allowing the water to run until the water in the hose runs clear.
If the tank had a lot of sediments, it might take a while for it all to be flushed out. Just be patient and ensure that little if any sediments are coming out of the hose by the time you wrap things up.
If there are still sediments at the bottom, try vacuuming them out using a half-inch vinyl tubing.
8. Finish everything up
Aside from knowing how to flush a hot water heater, you also need to be aware of the steps to take to have your heater working as usual.
Below are the steps you take once you are done flushing your heater.
- Turn off the drainage valve and disconnect the attached hose.
- If you had opened the pressure release valve, close it. This would be a great opportunity also to replace a faulty release valve.
- Turn off the hot water taps you had opened in the tub or sink.
- Turn the cold-water valve leading to the heater on
- Once the water heater tank is full, open the pressure release valve to ensure that any excess air in the system is expelled.
- If you had shut the gas off, put it on. Turn the thermostat on if it was off or relight the pilot light and then turn the thermostat on.
- For an electric water heater, turn the breaker switch on and give your heater twenty or so minutes to heat the water.
- Turn any hot water in the house to see if the heater is working properly. There, your heater is free of sediments, and you can rest easy knowing that it is well protected until the next time.
How Often To Flush A Hot Water Heater?
Now that you know how to flush a hot water heater, you must ensure that this is done regularly to ensure optimal water heater performance.
The flushing frequency normally depends on the model. For most heaters, an annual flush is all it takes to keep a sediment buildup at bay.
For other models, flushing the system after every three years is adequate, especially if you have a water purifier.
Be sure to check the manufacturer recommendations where flushing is concerned and follow the recommended steps to the letter.
Now that you know how to flush a hot water heater, it will be much easier to keep your unit in perfect condition. Just ensure that you do this regularly and follow all steps, as highlighted above.