How to Drain a Hot Water Heater

March 15, 2021
Water Heater

Water heaters are essential appliances that constantly supply hot water for different purposes throughout your home. This appliance utilizes a large, insulated reservoir that always holds enough hot water for your needs. Over time, however, the minerals in the water, sand and the debris flushed from the main water systems may settle at the bottom of the holding tank. Their accumulation may cause serious issues that could hamper the efficiency of your water heater. Its capacity may be reduced, the drain could become clogged and the water heater’s components may fail.

For example, these sediments may eventually cover the elements of the appliance, which prevents the transfer of heat from the burner to the heating components. As a result, the water heater would consume power, but it would not heat or keep the water warm. This would result in energy and money wastage.

Luckily, this problem can be eliminated by flushing the water heater. The process extends the appliance’s lifespan while keeping it highly efficient.

According to most water heater maintenance manuals, draining a water heater should be done every 6 to 12 months. This recommendation is to ensure that any buildup of sediment in the tank is removed. A buildup prevents your water heater from working efficiently.

Draining a water heater is relatively easy. But first, it is important to know what to expect before you begin the process.

What Should You Expect?

Leaks will certainly occur. Once you open or dismantle the water heater to flush it, the drain valve may not properly close again. If, for instance, the drain valve has seen better years, the less likely it will fit back in place impeccably. As a precaution, be prepared to cap the valve or have a ready replacement. Also, if your water heater had a cheap drain valve, this is your chance to give it an upgrade.

The tools you will need to drain the water heater include a garden hose and a flat-headed screwdriver. These are the steps you’ll need to drain a water heater.

1. Carry Out a Quick Flush

The first step to draining a water heater is performing a quick flush. Bring a garden hose and connect it to the drain valve. Then flush the holding tank when the pressure is on. To perform this function, open the drain valve for a few moments and then close it. The high pressure will eject any sediment lodged in the valve, helping the water heater to drain faster. You can repeat this process several times.

2. Turn Off the Water Supply

Before turning off the water supply, make sure that you shut off the gas to the system. If it is an electric water heater, turn the switch off to ensure that there are no exposed heating elements. These heating elements could burn out easily when the water level drops. Remember, many electric water heaters incorporate their own circuit breaker. You can find its switch in the main electrical panel.

Next, turn off the water from the primary water supply valve to the house or from the cold water valve above the water heater. For this step, it is important to check that the pressure is turned off. This is because for both gas and electric water heaters, even with the heating elements completely turned off, the water can remain hot in the tank for hours!

Test to check if it is completely off by having the water faucets run in the house; turn them on and off to check if there is any hot water. The easiest way is to give it a few hours, or you can wait overnight for the water to cool down before carrying on. If you cannot wait for the water to cool down, take extreme caution while draining the scalding hot water.

3. Attach the Garden Hose to the Drain Valve

Close to the bottom of the reservoir, find the water heater’s drain valve and open it. Remember, some drain valves have a cover over the opening. Ensure that it is open, then connect the hose. Lay it out in a floor drain where it can drain safely. If the water is still hot, take extra measures to prevent accidents.

4. Open the Hot Water Tap

Normally, attaching the garden hose to the drain valve may not amount to much drainage unless the vacuum in the tank is released. To do this, detach one end of the hot water pipe at the top of the water heater and pull it a bit to the side. This will alleviate the pressure by allowing air to enter the tank, which initiates efficient drainage.

5. Open the Drain Valve

Once the pressure from the water heater is alleviated, open the drain valve to allow the sediments to be flushed out of the tank. Keep in mind that the water may still be hot, so exercise extra caution. After all the water in the water heater has been drained, briefly run the cold water through the tank to strip it of any remaining sediments. Repeat this process several times until the water runs clear. If the sediment buildup is severe and has blocked the opening of the drain valve, call an expert for professional help.

6. Close the Valve, Refill the Tank and Restart the Water Heater

After the water runs clear, close the drain valve, detach the garden hose and switch on the cold water supply. Then, find the hot water tap you had detached earlier and reconnect it. Run the water and allow it to fill the tank. Ensure that it is properly tightened. Now, turn the water on, and allow the reservoir to fill. Turn on a hot water fixture such as the hot bathtub faucet and leave it running until all the air is out of the lines and nothing but water is running. Then, turn off the water.

Next, relight the water heater by turning the gas valve back on from the pilot position. If the water heater is electric, switch the power back on from the circuit breaker or the main unit. In an hour or so, your system will begin dispensing hot water.

Before finishing the process, check the drain valve for leaks. If the drain did not close correctly, put a cap over it or install a replacement.

The process may seem simple, but extra precautions must be considered. For example, some tanks must be completely filled with water to prevent potential damage to the gas burners or heating elements. It is, therefore, important to follow the manufacturer’s directions and warnings before proceeding.

While at it, don’t forget to look out for rusty-looking water or reduced amounts of hot water in your faucets. These are some of the indicators that you probably need a water heater replacement. If you’re having these problems, call a professional for a proper diagnosis and recommendation.

Schedule a Service Call

If you need more information on how to drain your water heater or are looking to install a new one, call C & C Heating & Air Conditioning today in Roseville, MI. We are your go-to solution for all your air conditioning needs in Center Line, Clinton Township, Macomb Township, Mount Clemens, New Haven, Berkley, Birmingham, Bloomfield Hills and the surrounding areas.

With over six decades of experience in installing and servicing all makes and models of heating and cooling equipment, we aim to exceed client expectations by providing the best services that save you money. We also offer duct cleaning services and UV lights. Call us today!

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