So, you want to flush your water heater’s tank but need to know how long it takes? You’ve come to the right place.
In fact, we’re going to tell you why it needs to be done. We’ll even show you how to drain your water heater tank properly. As a bonus, we have a video below if you prefer watching and listening.
Why Should I Drain My Water Heater?
Did you know that sediment accumulates at the bottom of your water heater? It does. And this leads to clogging and a poorly performing water heater. By removing the water, you’re also removing the sediment. This is called flushing the tank.
Minerals like calcium and magnesium combine to form sediment, which settles to the bottom of your water heater tank. Unfortunately, the sediment builds up and decreases the efficiency of your system.
Water temperatures become inconsistent, energy bills get higher, and even your supply of hot water gets lessened. You might even experience maintenance problems that require a plumber. Don’t ignore any sounds you hear coming out of your tank. It might mean you need to flush it out, or something more problematic and expensive.
How Long Does it Take to Drain a Water Heater?
It only takes about 15 to 30 minutes to completely drain a water heater.
A typical 40- to 60-gallon residential tank found in most homes will take no more than 15 minutes. However, larger tanks (80 gallons or more) found in homes with larger families can take longer, usually from 30 to 60 minutes; sometimes more.
Keep in mind, removing (draining/flushing) water from the tank is the quickest part of the job. There is also refilling the tank, which can take about an hour or two. And don’t forget about the preparation involved, such as attaching a garden hose to the drain valve and making sure you have a large bucket to pour the sediment into.
How Often Should Your Drain Your Water Heater?
It depends. If your home uses hard water (which most areas of the country do), then you should ideally drain and flush your water heater about once every 3 months, but at least once every six months.
If you have soft water, or a whole-house soft water filtration system, then you can flush and drain the tank once every year or two. You might not even have to do it that often, as the soft water by its nature does not include minerals that harden and build up.
How to Drain a Water Heater Tank?
- Turn the gas control knob to OFF and close the gas shutoff valve. For an electric water heater, shut off the power at the main service panel.
- Close the cold water supply valve and open a hot water faucet in the house to speed draining.
- Attach a hose to the drain valve and run it to a nearby floor drain or into a bucket beneath the drain valve.
- Turn the drain valve clockwise to open it.
- As the tank empties, the valve may clog with sediment: if so, open the cold water supply valve for a few minutes to allow the water pressure to clear the blockage.
- If you are using a bucket, watch carefully and turn the drain valve off before the bucket overflows; the process might take up to an hour.
When I’m Done, How Do I Refill the Tank?
- To refill the tank, close the drain valve tightly, open the cold water supply valve and open the hot water faucet farthest from the tank.
- When water flows from that faucet, the tank is full and you can close the faucet.
- Be sure the water heater tank is full before turning on the gas or electricity, then relight the pilor or turn the power back on.
- 2 or 3 gallons can be drawn off in this manner every few months to check for sediment.
You should never take for granted your water heater’s performance. It can be diminished by the amount of sediment that builds over time. And it can build up quickly, in 2-3 months in many cases. If you can’t afford a plumber to handle this maintenance for you, it’s easy enough that you can do it on your own. Just follow the steps above.
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1-Tom-Plumber’s certified team of plumbers and drain technicians respond immediately to any emergency plumbing, drain cleaning, or water damage problem. We also handle the excavation of underground water lines and sewer main lines. Our immediate-response team is available every day and night of the year, even on holidays.