How to Flush Your Hot Water Heater

How to Flush Your Hot Water Heater with J&A South Park of Pittsburgh, PA.

Do I Need to Flush My Hot Water Heater? Absolutely!

No modern convenience is more lavish than a long, hot shower. But while you’re relaxing under the spray, do you ever consider its source? Do you know that if your water heater hasn’t been well maintained, mineral deposits like rust may have built up inside it? They might just make that long soak less enjoyable than you were hoping for.

Your water heater is one of those appliances that’s comparatively uncomplicated and easy to take for granted. After all, it’s out of sight, out of mind, and can perform its job for years on end without any maintenance at all. You might only think of it when something goes awry.

Truth is, like most appliances, water heaters require regular maintenance to maximize energy efficiency and extend the unit’s lifespan. A neglected water heater just might keep the hot water flowing for a few years but will slowly but surely trigger higher utility bills. Eventually, the unit will fail altogether.

The best way to safeguard your investment is to have your water heater serviced once a year by a licensed professional plumber. A good plumber will perform a complete inspection for rust, leaks, and other problems, test the thermostat and valves, replace the anode rod to stop corrosion and, finally, flush the tank.

But this last chore– flushing the tank – is one you just may want to carry out yourself as often as every couple of months, depending on the mineral content of your local water supply. Learning how to flush a water heater on your own can save you a lot of money over time. And it’s really not that difficult.

Why should I flush my water tank periodically?

Flushing out the lime and other sediments in the water heater tank regularly increases the heater’s efficiency and lifecycle In neglected heaters, sediment can pile up and calcify, making it hard to remove. This can get so bad at times that the entire water heating unit may need to be replaced. But if you flush your tank regularly, you can prevent sediment from causing these types of problems.

All water has a certain measure of mineral content. For example, suppose you live in an area with plenty of limestone beneath the ground. In that case, the groundwater will pick up calcium and magnesium deposits, giving rise to so-called “hard” water.

Hard water produces sediment in the form of limescale that eventually builds up at the bottom of the water tank. With natural gas, heaters can cause uneven heating in the tank that might even produce leaks over time. With electric heaters, scaling can burn out the lower heating element. And in both types of heaters, sediment buildup can plug up the drain valve.

How do I recognize sediment buildup? One symptom of excessive sediment buildup is a popping or rumbling sound coming from the heater’s tank. That’s the sound of steam bubbles percolating up through the muck. In addition, the sediment produces hot spots on a gas water heater that can damage the tank and eventually lead to early heater failure.

When will I know my water heater needs a flush?

Thank goodness the water supply to your water heater is filtered to some degree before it reaches your home. Otherwise, your hot water tank would fill up with sediment in practically no time at all. You might not detect any accumulation, as it could take years.

Eventually, however, you’ll notice that you’re getting less and less hot water from the tank before it runs out. If you’re within easy reach of the water tank, you can perhaps see the sediment coming out of the drain valve unless the sediment has already plugged the valve.

A word of advice: If you haven’t flushed your water heater in several years, you may be better off getting a licensed plumber to do the job. You run the risk of activating potential leaks. You see, it’s quite possible the sediment that has been there for years has produced cracks in the bottom of the tank. The existing sediment is plugging those cracks for now, but once you drain and flush the tank, it may well get rid of the sediment that is “sealing” the leaks.

By no means are we recommending that you shouldn’t drain your tank, and we’re also not suggesting that if you haven’t flushed it in several years, you’re going to have a leak in the tank necessarily.

However, by contacting a licensed plumber to do the job, if it does happen to leak, you’ve got the right person at hand to cope with it.

Flush your hot water heater

Okay, it’s time to flush that water heater.

Here then, is a step-by-step approach to flushing your water heater.

Step 1: Turn off the water heater and water supply

First, you’ll need to switch off the cold-water supply valve on your water heater. Atop the water heater, you’ll see a water pipe and a shutoff valve going into the heater. Turn this valve to shut off the water to the tank. You may need to turn off the water where the main supply line enters your house in older homes.

If your water heater is gas, position the thermostat on pilot. If your heater is electric, shut the power off your home’s electrical panel. The correct fuse or circuit breaker should be labeled as being connected to the water heater.

As a precaution, it’s a good idea to let your water heater sit a while, so the water in the tank has the chance to cool down.

Step 2: Connect a garden hose to the drain valve.

Once your water heater has cooled down, place one end of the hose (you can use a conventional garden hose) into a floor drain or, if it will reach, directly outside. Attach the other end onto the drain valve at the bottom of the heater.

Step 3: Run hot water and open the drain valve.

Open the hot water tap, similar to a sink faucet that is closest to the water heater. This helps ease pressure and lets the tank drain faster. Once you open this valve, the water will flow out of the tank. Be patient, as it may take a bit to drain if the tank is full or there is a considerable amount of sediment.

Step 4: Turn the water supply back on to flush the tank.

With the drain valve still open, turn the cold water back on to help do away with any residual sediment on the bottom of the tank. Repeat this step until the water runs clear.

Step 5: Close drain valve, fill tank and turn on water heater.

Now that the tank has been drained close the drain valve again and detach your garden hose. Be sure your cold-water supply valve is on, and the tank will begin to refill. Return to the hot water tap you’ve been running, wait for cold water to start running, and turn it off. Turn the gas back on for your gas heater or flip the breaker in your breaker box for electric water heaters. Check the valve for any leaks, and, voila, you’re done.

Some tanks must always be full, so check your manufacturer’s directions to steer clear of any damage to the heating elements. If you detect any issues with your water heater’s operation, give us a call, and we’ll have one of our techs come out for an inspection.

What if my tank won’t drain?

Suppose your tank is draining slowly or not at all; attempt to open the temperature/pressure relief valve on the hot water tank. This is situated near the top of the hot water tank. It’s generally a lever you can lift up or down, and there is a pipe that goes from it down to the base of the tank. Opening up this valve might open up a possible vacuum inside the tank that’s stopping water from draining.

It’s also likely that there’s so much sediment inside your tank that it’s blocking the valve drain. This is where calling a licensed plumber is the best strategy.

Below is a brief video on how to flush your water heater!

What exactly are the benefits of draining your hot water tank?

  • Noise reduction: Over time, when mineral or scale has accumulated in your hot water tank, you’ll most likely hear banging, crackling or popping sounds. For the time being, the noise may diminish without your doing anything to the tank; that’s because the scale layer has hardened, and it’s tough for water to percolate through it effortlessly. However, when you do drain and descale the tank, it will no longer produce those noises when working.
  • Enhanced efficiency: As additional debris lands on the bottom of the tank, it turns out to be more difficult for heat to transfer because these deposits have perched on the heater’s electrodes. Draining the water tank will remove the sediments, and the heating speed will recover.
  • Reduced energy bill: As just noted, the appliance consumes more energy to heat water when scales have built upon its electrodes. By removing the dirt and scales, the heater’s efficiency will improve and reduce the energy used during the process. Hence, a reduced energy bill.
  • Longer life: By draining your hot water tank on a regular basis, you’re simply removing scale that causes the appliance to experience stress. Consequently, the metal in the bottom of the tank can get hotter than normal and start to leak or fail. But, as we’ve seen, constant draining and flushing will increase the lifespan of the appliance.

What if I have a tankless water heater?

The process we’ve just explained applies to conventional hot water tanks, but tankless water heaters are also subject to damage from sediment. There is a completely different process for tankless heaters that involves a pump to circulate water through the system. You can usually pick up a tankless water heater flush kit at your neighborhood hardware store.

What if my water heater is simply too old?

While wine might get better with age, water heaters certainly do not. There will come a time when you simply must replace your water heater because it’s just too old to work properly.

Get rid of sediment in hot water heater

So, how long should I expect my present water heater to last?

Water heaters are limited to an average of eight to ten years. Every ten years is the most recommended time to replace your heater, but you must also remember that different types of water heaters have varying life expectancy’s. For example, gas heaters normally last six to eight years.

So, when you talk about old being gold, give a hall pass to your water heater.

If a problem should arise with your water heater, don’t hesitate to call the professionals at J&A South Park. They can offer the highest standards in repair and, if necessary, replace your existing tank with a new heater. Of course, we can also provide the yearly inspection for your tank.

And while we’re here, the management and staff at J&A South Park want to wish each of you the happiest of holidays and nothing but the best for the coming new year.

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