How to flush a water heater

When it comes to doing household chores, flushing your hot water heater is easy to overlook. I know I never thought about doing it until Jeremy included it in his truly handy home maintenance checklist.

But regularly flushing out your hot water heater is an important task. Getting rid of the gunk and mineral deposits that accumulate will help your hot water heater run more efficiently as well as prolong its life, saving you money in the long run.

After living in my home for several years, I figured my hot water heater was due for a flush and decided to tackle this chore. Fortunately, it turned out to be super easy. Excluding the time I was waiting for the water in the tank to cool, it took me all of about 20 minutes.

I documented the process as I did it, just in case you need to do likewise. Maybe this post will inspire you to finally knock this to-do off your list this weekend.

How Often Should You Flush Your Hot Water Heater?

Depending on your model, aim to flush your hot water heater every one to three years. Really, the job is so easy, it wouldn’t be a bother to do it at least once a year.

How to Flush Your Hot Water Heater

Hot water heaters come in two varieties: gas and electric. I’ve got the gas variety, so these instructions will be geared towards flushing a gas hot water heater. The biggest difference between gas and electric is that with gas, you’ll be turning off the gas to your appliance; with an electric, you’ll be turning off the electricity.

1. Turn the Knob on Your Hot Water Heater’s Thermostat to “Off”

How to flush a water heater

The thermostat on a gas hot water heater is usually found near the bottom of the tank. Other sources I ran across said you could get away with just setting your thermostat to “Pilot.” I decided to be extra safe and turned it off completely. If you turn your hot water heater off, and you have an older model, you’ll have to re-light your pilot light.

If you have an electric hot water heater, you’ll want to find your home’s breaker box and turn off the switch that gives power to your hot water heater.

2. Turn Off Gas to Hot Water Heater

How to flush a water heater

If you have a gas hot water heater, find the gas pipe leading to your thermostat and pilot light and turn the valve to the off position. If you decide to just turn your thermostat to “pilot” you won’t need to do this step.

3. Turn Off the Cold Water Supply to Hot Water Heater

How to flush a water heater

The cold water valve is usually near the top of your hot water heater. Turn it to off.

4. Turn on the Hot Water in a Sink or Tub

How to flush a water heater

Leave them on during the entire flushing process. This will help prevent a vacuum from forming in the lines while you’re draining the hot water tank.

5. Connect Garden Hose to Drainage Spigot

How to flush a water heater

Before you turn on the spigot, make sure the other end of the hose leads outside or at least into a bucket. If your hot water heater is in the basement, you may need to get a portable pump in order to pump water out of the basement and to the ground floor.

6. Turn on Spigot and Drain

How to flush a water heater

Drain your tank until the water runs clear and no longer has sediment. If your tank has a lot of sediment, you may need to drain it completely. As you can see in this picture above, the water when I first started draining was a bit brown and there was a lot of sediment at the bottom of the bowl.

8. Flush

How to flush a water heater

To flush your hot water tank, simply turn on the cold water spigot leading into your hot water tank. Let it run for a few minutes until the water exiting your hose runs clear.

How to flush a water heater

This may take a bit. While the water might be running clear and isn’t brown, you may still have some sediment. Here’s a picture of the water coming from my tank when I first started flushing:

How to flush a water heater

As you can see, I still had some sediment (can be seen at the bottom) coming out. Continue flushing until you have very little or no sediment in your water. Turn off the cold water spigot leading into your hot water tank.

Finishing Things Up

  • Turn off the drainage spigot and disconnect hose.
  • Turn off the water on your sink or tub that you turned on at the beginning.
  • Turn on the cold water spigot leading to your hot water heater.
  • Turn on the hot water spigot of a sink or tub to get the air out of the system. Cold water should be coming out of the faucet at this point. Turn it off.
  • If you shut off the gas to your hot water heater, turn it back on.
  • If you turned the thermostat off on your hot water heater, re-light the pilot light (it’s easy — I may do a post on this in the future), and then turn it to on.
  • If you have an electric hot water heater, flip the breaker switch on your electrical panel that gives power to your hot water heater.
  • Wait about 20 minutes for the water to heat up. Turn on a hot water spigot somewhere in your house to ensure hot water is coming out.

Boom. You’ve flushed your hot water heater. Put it on your calendar to do it again in a year.

When it comes to doing household chores, flushing your hot water heater is easy to overlook. I know I never thought about doing it until Jeremy included it in his truly handy home maintenance checklist.

But regularly flushing out your hot water heater is an important task. Getting rid of the gunk and mineral deposits that accumulate will help your hot water heater run more efficiently as well as prolong its life, saving you money in the long run.

After living in my home for several years, I figured my hot water heater was due for a flush and decided to tackle this chore. Fortunately, it turned out to be super easy. Excluding the time I was waiting for the water in the tank to cool, it took me all of about 20 minutes.

I documented the process as I did it, just in case you need to do likewise. Maybe this post will inspire you to finally knock this to-do off your list this weekend.

How Often Should You Flush Your Hot Water Heater?

Depending on your model, aim to flush your hot water heater every one to three years. Really, the job is so easy, it wouldn’t be a bother to do it at least once a year.

How to Flush Your Hot Water Heater

Hot water heaters come in two varieties: gas and electric. I’ve got the gas variety, so these instructions will be geared towards flushing a gas hot water heater. The biggest difference between gas and electric is that with gas, you’ll be turning off the gas to your appliance; with an electric, you’ll be turning off the electricity.

1. Turn the Knob on Your Hot Water Heater’s Thermostat to “Off”

How to flush a water heater

The thermostat on a gas hot water heater is usually found near the bottom of the tank. Other sources I ran across said you could get away with just setting your thermostat to “Pilot.” I decided to be extra safe and turned it off completely. If you turn your hot water heater off, and you have an older model, you’ll have to re-light your pilot light.

If you have an electric hot water heater, you’ll want to find your home’s breaker box and turn off the switch that gives power to your hot water heater.

2. Turn Off Gas to Hot Water Heater

How to flush a water heater

If you have a gas hot water heater, find the gas pipe leading to your thermostat and pilot light and turn the valve to the off position. If you decide to just turn your thermostat to “pilot” you won’t need to do this step.

3. Turn Off the Cold Water Supply to Hot Water Heater

How to flush a water heater

The cold water valve is usually near the top of your hot water heater. Turn it to off.

4. Turn on the Hot Water in a Sink or Tub

How to flush a water heater

Leave them on during the entire flushing process. This will help prevent a vacuum from forming in the lines while you’re draining the hot water tank.

5. Connect Garden Hose to Drainage Spigot

How to flush a water heater

Before you turn on the spigot, make sure the other end of the hose leads outside or at least into a bucket. If your hot water heater is in the basement, you may need to get a portable pump in order to pump water out of the basement and to the ground floor.

6. Turn on Spigot and Drain

How to flush a water heater

Drain your tank until the water runs clear and no longer has sediment. If your tank has a lot of sediment, you may need to drain it completely. As you can see in this picture above, the water when I first started draining was a bit brown and there was a lot of sediment at the bottom of the bowl.

8. Flush

How to flush a water heater

To flush your hot water tank, simply turn on the cold water spigot leading into your hot water tank. Let it run for a few minutes until the water exiting your hose runs clear.

How to flush a water heater

This may take a bit. While the water might be running clear and isn’t brown, you may still have some sediment. Here’s a picture of the water coming from my tank when I first started flushing:

How to flush a water heater

As you can see, I still had some sediment (can be seen at the bottom) coming out. Continue flushing until you have very little or no sediment in your water. Turn off the cold water spigot leading into your hot water tank.

Finishing Things Up

  • Turn off the drainage spigot and disconnect hose.
  • Turn off the water on your sink or tub that you turned on at the beginning.
  • Turn on the cold water spigot leading to your hot water heater.
  • Turn on the hot water spigot of a sink or tub to get the air out of the system. Cold water should be coming out of the faucet at this point. Turn it off.
  • If you shut off the gas to your hot water heater, turn it back on.
  • If you turned the thermostat off on your hot water heater, re-light the pilot light (it’s easy — I may do a post on this in the future), and then turn it to on.
  • If you have an electric hot water heater, flip the breaker switch on your electrical panel that gives power to your hot water heater.
  • Wait about 20 minutes for the water to heat up. Turn on a hot water spigot somewhere in your house to ensure hot water is coming out.

Boom. You’ve flushed your hot water heater. Put it on your calendar to do it again in a year.

How to flush a water heater

Did you know that many homes in Omaha, Nebraska have water with an average hardness of 10 grains per gallon? This means that the water contains high concentrations of calcium carbonate (CaCO3). CaCO3, in turn, is a key component of limescale, the hard, chalky deposit that builds up in water heater tanks.

Per the US Department of Interior and the Water Quality Association, 10 gpg is hard water. Hard water may not be a health threat, but it can reduce your water heater’s efficiency and service life.

Learning how to flush out a water heater the right way can help you keep it in tip-shop shape. We outline the basic steps on how to clean a water heater in this guide, so be sure to read on!

Determine the Last Time You Flushed Your Tank

Most water heaters have a service life of eight to 12 years. However, this still depends on regular maintenance, including flushing it twice a year. If you haven’t drained yours in a long time, hold off on doing so, as it could trigger tank leaks.

That might happen if the tank has interior fissures now covered with limescale. Flushing your tank could remove some of those mineral deposits and expose the cracks. If this occurs, your tank could start leaking water from the bottom.

In that case, it may be best to call a plumber instead of flushing the tank yourself. A licensed plumbing expert has the eyes and the tools to discern potential leaks.

Turn Off the Water Heater’s Power Supply

If your heater is only about one year old, you can go ahead and flush it. Before you do so, switch off the gas or electrical power that supplies energy to your tank. This is for safety purposes, as it can help prevent accidental gas leaks or shock injuries.

Do note that in the US alone, some 30,000 non-fatal shock injuries take place each year.

If you have a gas-powered heater, simply switch the control to “Pilot” mode. If you have an electric heater, you can cut its power supply by switching off its circuit breaker. You can find this breaker in your main electrical panel.

It’s also a smart idea to wear rubber insulating gloves and anti-slip footwear. A face mask and goggles can also protect you from the dust and debris that you’re likely to stir up as you clean the tank.

Close the Cold Water Valve

Many water heaters have color-coded valves to distinguish hot from cold inlets. If yours is color-coded, the cold water valve should have a blue handle.

If your heater’s valves aren’t color-coded, take a closer look at the valves themselves. They should have a label or mark that indicates whether they’re for the hot or the cold water supply.

Let Your Tank’s Contents Cool Down

More than 450,000 burn injuries requiring medical treatment occur in the US each year. Many of these injuries take place within homes.

Now, since you’re flushing the water heater tank itself, you want to be extra careful. It’s best to wait for a few hours to let the water inside the tank cool down before you drain it. Doing so can help reduce your odds of scalding yourself.

If you can’t wait that long, consider booking a quick water heater service request. This way, you can have a licensed plumber come to your aid right away and perform the heater maintenance for you.

Connect a Hose to the Tank’s Drain Valve

Near the very bottom of your water heater tank is a drain valve either made of plastic, composite, or brass. You can connect one end of a hose (a garden hose would do) to this valve after waiting for a few hours for the water to cool down. Run the other end to a floor drain, or if it’s long enough, outside of your home.

The most important thing is to make sure the open end sits at a lower level than the one connected to your tank. This helps ensure that gravity can do its work, which is to push the water from inside the tank to the other end of the hose.

Let It Drain

At the top of your heater is another valve called the temperature and pressure (T&P) relief valve. It’s a safety component that opens and releases excess heat and pressure from within the tank.

Open the T&P valve, plus another hot water faucet in the house, to enable air to enter the tank. Next, open the drain valve itself. The air will work hand in hand with gravity to push the water inside the tank out of the drain valve.

Give your heater several minutes so that it can empty its contents. Monitor the last bit of water that drains, too, as it may still contain sediments. If so, open the cold water supply valve to let a couple more gallons of water run through the tank.

Refill the Tank

Once the water that leaves the tank is clear, close the T&P valve, drain valve, and hot water tap you opened. Remove the hose you attached to the drain valve. Wipe any areas that may have gotten wet while you were flushing the tank.

Next, open the cold water supply valve so you can start refilling the water heater tank. Allow the water to flow for about 15 minutes before you run a nearby hot water tap. Doing so can help release any remaining air from within the tank and the plumbing pipes.

You can expect the water coming out of the hot water faucet to be full of air bubbles. As soon as this clears, close the tap and restart your water heater.

Follow These Expert Tips on How To Flush Out a Water Heater Today

As you can see, there are several steps to take in order to flush out a water heater the right way. If you’re not confident of your DIY skills, it’s best to leave this task in the hands of the pros.

If you’re in Omaha, NE, or nearby, you can put your trust in our team of plumbing professionals here at Eyman. Get in touch with us today at (402) 731-2727 so that we can help you flush and service your water heater.

How to flush a water heater

When the water comes out of the faucet hot, it’s easy to take your water heater for granted. But one cold shower can provide a stark reminder of the importance of this appliance in your everyday life.

A typical water heater will last between eight and 15 years before it needs to be replaced. Over the course of that lifespan, various maintenance needs and equipment malfunctions may disrupt the steady flow of warm water into your home. When problems arise, one of the common remedies is to (flush the water heater) and see if a reset of the appliance solves the problem.

Sometimes the water heater starts working again like new, and other times the drain and flush fails to make a difference. Either way, it’s helpful for homeowners to know (how to flush a water heater) so that they can troubleshoot the appliance before calling in a professional.

Read on to discover the common problems that can develop in water heaters, and to find out (how to flush a hot water heater).

Why Would You Need to Flush a Hot Water Heater?

Flushing a water heater provides a basic reset of the appliance’s heating process—and can help clean out buildup that may be affecting its performance. Typically, a water heater may need to be flushed due to the following reasons:

  • To remove sediment buildup from inside the water heater. This is the most common reason to flush out a water heater.
  • To eliminate mineral scale buildup. This buildup can accumulate faster if your water heater is fed by a hard water source.
  • To improve heating speed. A clean water heater will heat up water faster—which also reduces energy consumption and saves money on your utilities bills.
  • To ensure the appliance warranty remains valid. Some water heaters come with a warranty that is invalidated if the homeowner does not maintain regular flushing and cleaning of the appliance.

To benefit from regular maintenance, experts suggest flushing out your water heater every six to 12 months. This will remove sediment on a regular schedule, before it accumulates and causes additional problems in your home.

How to Drain a Water Heater

Before you can flush out the water heater, you need to turn off the appliance and drain the existing water from the tank. Start this process by shutting off the gas supply on a gas water heater, or flipping the power switch on an electric heater.

Once the appliance is off, connect a garden hose to the drain valve and run the hose to a drain in the floor or your home. Open up the drain valve, then remove the hot water pipe at the top of the water heater to ventilate the tank, which will allow it to drain faster. Allow the water heater to fully drain before you begin flushing.

How Do You Flush a Water Heater?

Once the water has been emptied out, the process of (how to flush out a water heater) is quick and easy. With the drain hose still attached, turn on the water and allow it to run for a minute before turning it off. Allow the water to fully drain out of the water tank, then repeat this process again. You should do this several times to flush out the sediment that has accumulated in the water heater. If you suspect significant buildup, or you haven’t flushed out your water heater for more than a year, continue this process until the drainage coming out of your garden hose appears to be clean.

Once you’ve finished flushing the water heater, close the drain valve and remove the garden hose. Replace the hot water pipe and seal it shut, then turn on the water to allow the tank to refill. Once the tank has filled, restore heat to the appliance by flipping the power switch on an electric water heater, or by lighting the pilot light on a gas heater.

Keep in mind that it could take an hour or longer before the water heater is able to fully heat its tank. Make a plan to forego showers or other hot water needs until the heating process is complete.

After this heating period is finished, check the heat of your water by running one of your hot water faucets. If hot water has returned, the water heater is back to normal. If the water is lukewarm or cold, there may be another problem with your water heater that the flushing was unable to address.

Still Having Problems After You Flush a Water Heater Tank?

While flushing a water heater should fix a lot of problems that may have developed in the appliance, it’s possible that a full drain and flush won’t solve whatever is wrong with your water heater. If this is the case, contact an indoor plumbing specialist to have the water heater thoroughly inspected. This professional can then repair the water heater or recommend a replacement if it’s time to purchase a new one.

By knowing the basic maintenance requirements for your water heater, you can troubleshoot simple problems and save yourself a visit from an expert. Just make sure you know your limits when it comes to DIY repair: when in doubt, call in an expert with the experience you need to solve your water heating problem.

Tankless water heaters can be a large financial investment. Learning how to flush them properly can be a big return on your investment.

Tankless water heaters can be a large financial investment. So learning how to flush them properly can be a big return on your investment.

Properly flushing your tankless water heater can make sure that you get the maximum efficiency with your installation. Read on to learn more about how to install a tankless water heater .

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Do Tankless Water Heaters Need to Be Flushed?

Tankless water heaters can fill with calcium and other mineral debris from the water. To keep your machine efficient and in good working order, you should try to flush it once every year to a year and a half. Flushing will clear out the filter inside the machine so it can properly filter water again.

Among other things, flushing your water heater can:

Failing to flush your heater on a regular basis can reduce efficiency and lead to problems down the road.

How to flush a water heater

What Happens If You Don’t Flush Your Tankless Water Heater?

Most water contains mineral deposits in it. These mineral deposits can settle in your tankless water heater filters. The more minerals in these filters, the less efficiently the heater can do its job.

Tankless water heaters that do not get flushed build up considerable residue on their filters, reducing the efficiency of the machine. Failing to flush your tankless water heater on a regular basis can lead to:

A broken water heater can be a costly replacement, so you should get in the habit of regularly flushing your system.

How Often Should You Flush Your Tankless Water Heater?

You should flush your tankless water heater at least once every 12 to 18 months. Any longer than that, and mineral residue on your filters can severely impact filter performance.

Depending on the water content in your location and the frequency of heater use, you may have to change your filter earlier than once every 12 months. Common signs that you need to change filters include:

Failing to flush your heater can lead to long-term problems and can permanently damage the unit.

Preparing a Tankless Water Heater for Flushing (Safety Precautions & Tools)

Before starting working with your tankless water heater, here are a few safety precautions and tools to keep in mind.

How to Flush a Tankless Water Heater (Step-By-Step Guide)

1. Gas-Powered Water Heater

2. Electric Tankless Water Heater

Tankless Water Heater Flush Kits

Several brands sell tankless water heater flushing kits that are designed to help you with the process. Most of the time, you do not need to purchase a kit, but they can be useful because they come with the hoses and cleaning solutions that you will need to use.

3. How To Flush Rinnai Hot Water Unit

Flushing a Rinnai water heater is not hard. First, close the hot and cold water shut-off valves. Then connect a pond pump and garden hose to the serviced valve. Flush a mixture of about 4 gallons of vinegar through the system, then connect a hose to the second service valve.

Place the end of the hose and the pump in the bucket. When done, remove the hoses and turn the shut-off valves back open.

How to flush a water heater

4. How To Flush Rheem Hot Water Unit

Turn off the electricity and gas supply to your heater unit. Then, turn the cold water supply off by turning the handle clockwise. Then thread a garden hose through the drain valve into the heater tank.

The drain valve on most Rheem units is on the lower part of the tank near the gas valve. Place the end of the hose outside and turn a faucet of hot water on.

Let the water drain from the heater and then open the cold water supply line. Let it run through the system out of the hose until the water is clear. Then, close the drain valve and let the tank fill with water. Remove the hose and reconnect the electrical and gas supply lines.

5. How To Flush A Navien Hot Water Unit

When it comes to flushing a Navien hot water unit this is what you need to do. Turn off the gas and electrical power lines. Then, remove the cover and unplug the unit.

Remove the cold air intake filter, clean it, and return it to its place. Then drain the water heater by turning off the cold and hot water valves—hooking hoses to the service valves and emptying the unit into a bucket.

Take the dirt trap out of your system and run vinegar through the pump system with a sump pump and hose setup. Flush the system, turn the valves open, replace the cover, and reconnect the power and gas to the unit.

6. How To Flush Noritz Hot Water Unit

Turn the gas of the unit off and turn the hot and cold water valves off. Remove the drain caps on both sides, turn the drain valve on, and let the unit drain into a bucket. Connect a hose to the pump and place it in the bucket.

Connect the other end of the hose to the cold water outlet. Connect another hose to the hot water drain valve and put the end of the hose into a bucket.

Flush the system with 4 gallons of vinegar for about 2 hours. Change the solution about halfway in. Remove the pump and cold water line hose, leaving the hot water line hose in. Open the cold water shut-off valve and let the system drain into the bucket.

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How to flush a water heater

Every homeowner knows how important it is to clean and maintain your systems and appliances. However, many homeowners don’t know that flushing a water heater every year can remove a build-up of sediment from the bottom of the tank. Flushing sediment can improve a water heater’s lifespan and efficiency. Sediment can create a barrier between the heating elements of the water heater and the water, making it harder to heat your home’s showers, dishwasher, and laundry. By flushing sediment out of your water heater, you can save money and heat your water faster.

Learn how a how a water heater works to better understand how to flush your tank.

1. Turn the Water Heater Off

How to flush a water heater

If you have an electric water heater, turn off the power switch. If your water heater is a gas heater like the one shown in the photo above, turn your thermostat to the “pilot” setting. This turns the heating element off in your water heater so your water can cool down. Before starting this maintenance project, make sure no one in your home is trying to take a shower, wash dishes, or run a load of laundry.

2. Turn the Cold Water Valve Off

How to flush a water heater

Turn the cold water valve off. A water heater moves hot water through your home when cold water is brought into the tank, displacing the hot water. Without the cold water coming into your tank, you can completely drain the tank of water. If you miss this step, you’ll end up having water continually move into the tank and drain, which could cost you a pretty penny on your water bill.

3. Let the water cool.

How to flush a water heater

Don’t drain scalding hot water. Let the tank cool after turning off the heating elements. This can take up to two hours for some larger water heater tanks.

4. Attach a drain or garden hose to the drain valve on the side of the tank

How to flush a water heater

Find the drain valve on the side of your water heater and attach a hose. Make sure the hose is threaded on completely or you could end up with leaks as you drain your water heater tank.

5. Place the end of the hose in a bucket or drain.

How to flush a water heater

Don’t flood your home! Make sure to put the end of the hose in a heat-proof bucket or down a drain. Before you begin draining the water heater, make sure that your drain isn’t going to overflow.

6. Turn on a faucet (or two)

How to flush a water heater

Opening faucets around your home can stop a vacuum from forming within your pipes. Turn your faucets on the “hot” setting and let them run. You won’t see a lot of water coming out of them because you’ve turned off the cold water valve to your water heater, so no warm water is being displaced.

7. Start draining the tank by turning on the drain valve.

How to flush a water heater

Using a flathead screwdriver, turn the valve on slowly, making sure that there aren’t any leaks and the bucket or drain you are draining the water into isn’t going to overflow.

8. After the water heater tank has finished draining the sediment, turn the drain valve off, remove the hose, turn the cold water valve on, and turn the heating elements in the water heater back on.

How to flush a water heater

After you’ve completely drained the tank, and removed the sediment within your water heater, you’re almost done! To fill your tank again, turn the drain valve off, and remove the hose. Turn the cold water valve back on and turn the heating elements back to the on position.

Make sure that your taps are still on, and once they return to a normal flow, turn them off. You’ll want to wait about 30 minutes to test for hot water. The water heater should have heated the gallons of water within the tank again, sediment free! Need more information on water heaters and why yours might not be functioning as well? Use our article about common water heater problems and how to decode them!

Landmark Home Warranty offers plans that cover water heaters (up to 70 gallons) if they fail from normal wear and tear. Some plans even cover for sediment damage! If your water heater has stopped working and you have a Landmark Home Warranty protection plan, you could get it repaired or replaced for just the cost of a service call fee if it is covered under the terms of your contract. Give us a call today or open a service request online.

How to flush a water heater

Relative to conventional house chores, flushing a gas water heater is a task that homeowners tend to overlook. What most homeowners don’t know is how crucial it is to flush a gas water heater. Removing mineral deposits and gunk from your heater will enhance its efficiency thus prolonging its service life. This also saves you money that would have been used for frequent replacements and maintenance works.

Flushing a heater is a simple activity that could take around 20 minutes or so. However, for some homeowners, it may seem like a tall order simply because they don’t know how to go about it.

In this article, we take you through a step-by-step guide on how you can flush your gas heater. If you’ve never done it before, put it on your bucket list for the weekend once you’re conversant with the steps. But first things first, let’s address some common concerns that people have over flushing gas water heaters.

How frequently should you flush your gas water heater?

The number of times you flush your heater largely depends on the model and size of the heater. Conventionally, it is advisable to do it once or twice a year considering the little effort needed to get the job done.

Why is it important to flush a gas water heater?

As time goes by, mineral deposits accumulate in form of sediments and scale on the water heater tank. These sediments can go as far as covering the entire base of your water heater. This in turn reduces the rate at which heat is transferred from the burner to the water tank, and this results in wastage of energy and money. It could also cause corrosion of the water tank.

Continued use of the heater without taking any effective measures will result in mineral deposits breaking free which will then block hot water from flowing through the pipes.

The blocks could also clog the valve that’s used to flush the water tank.

You should keep in mind that heaters that haven’t been flushed for years, aren’t fit for flushing since they could cause major leaks to your heating system. I would advise seeking help from a certified plumber that is within your location.

What are the costs for flushing a gas water heater?

Flushing a water heater could cost between $80 to $100 depending on the US. That may seem a little costly for such a simple task—but it’s worth the bucks. I’d recommend calling a plumber if your heater hasn’t been flushed for a while.

Steps on how to flush a gas water heater

Water heaters are available in two options; electric and gas heaters. The main difference between the two is that for electric heaters you’ll have to switch off the source of electricity while gas heaters just need to turn off the gas supply to undertake the flushing.

Here, we’ll focus more on how to flush gas heaters.

To ensure your procedure runs smoothly, follow the following steps;

On the thermostat of your heater turn the knob off

Most gas heaters have a thermostat located at the mid-section near the bottom of the tank. From the information we’ve gathered based on extensive research; you can set the thermostat on pilot mode. If you’re new to this, you should switch it off completely just to be on the safe side. For old heater models, don’t forget to re-light the pilot light at the end of the procedure.

Turn off the gas supply that’s directed to the heater

You’ll need to switch off the valve on the gas pipe that leads to the pilot light and thermostat. If you had earlier set the thermostat to pilot, you can skip this step.

Turn off the Cold-Water supply

At the top of the water heater, you’ll find the cold-water valve. Turn it off before proceeding to the next step.

On a sink or tub turn on the hot water outlet

You’ll have to leave them on throughout the entire procedure. This will eliminate vacuum buildup from messing up the process.

Turn on the pressure relief valve

This step is optional so you might as well skip it. However, going through with it will facilitate smooth water flow during the draining process and can also help in testing the pressure relief valve. Before you open the pressure valve, ensure you’ve placed a bucket underneath the drainage pipe since it could cause unnecessary spills on your work area.

You’ll also need to be extra careful given that the water coming out will be hot. If there is no water gushing out, this is enough indication that your pressure relief valve is faulty which means you need to replace it with a new one.

Make a connection between the garden horse and drainage spigot

Ensure that the hose is directed outside or into a bucket then you can proceed to turn on the spigot. You might consider using a portable pump if the heater is installed in your basement.

Proceed to drain

Also, be sure to drain the tank until there is no signs of sediments in the water. Depending on the amount of sediments, maximum drainage is advised.

Flushing

The final step is that you’ll need to flush the water tank by turning on the spigot for cold water which leads to the hot water tank. Leave it for a few minutes till the water coming out of the hose starts to run clear. This process requires patience since it might take a while. Once you’ve gotten rid of the sediments, the next thing is to turn off the spigot for cold water.

Cleaning and finishing your project

After finishing the task and you’re confident with the results, you can now put everything back in place. Make sure to close the hot water outlets and pressure relief valve that you had opened earlier. You should also fill up the hot water tank then open the hot water spigot to get rid of the air in the system. Lastly, give it 20 minutes or so for the water to get heated then check if the hot water is able to come out in any part of your house.

How To Flush A Gas Water Heater; Conclusion

As you noted, flushing a gas water heater doesn’t take some rocket science, and you can do it pretty fast. Follow the eight steps and we hope you’ll be done with it before you know it. In case you face any challenges, we’re always here.

Performing annual maintenance on a tank-style water heater by flushing it will extend its life and can prevent an expensive disaster from happening in your home.

Water heaters are one of the most essential appliances in your home. They’re a big investment, and most of our clients want to make sure they protect their investment for as long as possible. Performing annual maintenance on a tank-style water heater by flushing it will extend its life and can prevent an expensive disaster from happening in your home.

Flushing your water heater is easy and will remove the damaging sediment that can accumulate in the bottom of the tank after prolonged use. This sediment can block or clog your water heater's pressure relief valve (that prevents bursting) and can cause corrosion. Sediment can also make your water heater less effective by reducing its hot water output over time as well as making it less energy efficient.

Below is a simple guide to teach you how to flush your water heater:

Step 1: Turn off Gas or Electricity

If you have a gas water heater, turn the gas valve to the "off" position. If your water heater is electric, turn the electricity to the water heater off.

You must turn off an electric water heater completely before flushing or you will risk burning out the heating element.

Step 2: Shut off the Water

Shut off your water heater's water supply.

It’s important to wait for the water inside the water heater to cool before flushing as it can remain scalding hot. Start this step at night after everyone in your household has no need for hot water. If you’re not worried about the temperature of the water, go right to step 3.

Step 3: Open a Faucet

Open a hot water faucet somewhere in your house. If you want to drain your water heater faster, find the tub faucet as it likely has the highest flow rate in your home.

Step 4: Connect a Hose to the Drain Valve

For this step, you will need a hose that you will connect to the drain valve on your water heater. Then you will run the hose to a drain, either in your house or outside. A typical garden hose will be sufficient.

Step 5: Open the Drain Valve

Now that you have your hose all hooked up and positioned to a drain, open the drain valve on your water heater and allow the tank to completely drain.

Step 6: Turn Water Supply Back on and Flush

After your water heater tank is completely empty, turn the cold water source back on. Then, allow water to run through the heater and out of the drain valve for approximately 5 to 10 minutes.

You will know your water heater is successfully flushed when the water runs clear out of the hose.

Step 7: Refill the Tank

Now that your water heater is flushed and all the sediment has been removed, it’s time to refill it. You should close the drain valve and remove the hose. Then, with the cold water source still on, allow the tank to refill. You will know the tank is full when water begins to come out of the hot water faucet you have left open.

Congratulations! Now your water heater is successfully flushed and ready to perform at maximum efficiency again. Following these simple steps will help you get the most out of your water heater year after year.

If you have any questions about how to perform this maintenance, just give us a call. Our expert technicians are standing by ready to answer your questions.

If you’d rather watch a video, here’s our CEO, Ray, demonstrating how to perform annual maintenance on a tank-style water heater: