Learn How To Flush A Hot Water System In 7 Simple Steps

how to flush a water heater

Your hot water system can keep on producing reliable, hot and abundant streams of steaming hot water for your daily showers and baths for years upon years – as long as you do all of the right things. And one of those things, we’re here to tell you, is learning how to flush a water heater – and we can’t wait to show you how.

But before we get into how and why flushing hot water systems is the headline maintenance tip you simply must know about, what else should you know about looking after your system?

  • Visual/valve checks: How often do you look at your hot water system? If it’s been a while, give it a good occasional once-over, watching out for hot water system leaks & rust, operating the relief valve and checking on the pipes.
  • Anode rod: Did you know your storage hot water system almost certainly features a sacrificial anode rod? The principle is simple: the rod entices any rust or corrosion from your precious tank to the rod itself, so you’ll need to make sure it’s fresh at least once a year.
  • Plumbing inspections: DIY maintenance is one thing, but only the true hot water specialists can check every nook and cranny of your system including elements, piping, wiring and all the rest. We recommend an annual professional plumbing inspection.

How do you flush a hot water heater?

With all of that said, we know why you’re here – to learn all about why, how and how often you should flush a water heater so that it lasts as long as possible.

Let’s start with the ‘why’ and the ‘how often’ aspects of flushing water heaters:

The ‘why’:

Put simply, your mains water may seem clean & clear – but it’s not. To varying degrees, each water supply contains an array of minerals and contaminants. They may not hurt you, but over time the sediment build-up can very much hurt your hot water system. That’s why flushing water heaters is the single most important aspect of hot water system maintenance.

The ‘how often’:

Because hot water systems are not as cheap as chips, prevention is a lot better than cure. You may not notice the sediment building up, and it’s true that it may take years before you notice a single problem – but it’s crucial to look out for the signs.

Remember, even if your unit seems to be working just fine, we still recommend an annual plumbing inspection – because it’s going to work out a lot cheaper than a brand new unit in the end!

How to flush a water heater in 7 simple steps

It’s taken a while to get here, but we have finally arrived where we wanted to get to – understanding how to flush a water heater at home. It really is as simple as following these 7 easy steps:

1. Turn the system off

You don’t want your system trying to fill up the tank and heating water whilst we’re trying to flush it, but power it down also for obvious safety reasons. If it’s a gas hot water system, leaving the pilot light on is ok, just make sure no one is going to turn on the hot taps inside.

2. Turn off the water valve

Also turn off the cold mains water supply valve. This will ensure the tank can be completely drained.

3. Let it all cool down

It’s not much fun playing games with scorchingly hot water, so it’s a good idea to take a little break after powering down the system.

4. Attach a hose

Your garden hose will do the trick – it’s just a matter of attaching it to the tank’s drain valve. Just bear in mind that we’re about to drain the system, so the other end of the hose will need to be directed somewhere sensible.

5. Turn on a tap

Head inside and turn on one or two hot taps. This will get rid of any vacuums in the plumbing.

6. Turn on the drain valve

It’s time for action! Open up the drain valve slowly, checking for leaks and ensuring the water starts to drain in a controlled way.

7. Finish the job

With all the water now out:

  • Close the drain valve
  • Remove the hose
  • Turn the mains valve on
  • Turn the system back on.

Your system will now replenish the tank with fresh water – and hopefully, it’s close to 100% sediment free! Congrats!

Need a true professional in flushing water heaters?

Did you know the hot water experts at Fawcett Plumbing can step your hot water system maintenance up a notch with a professional and incredibly thorough hot water system flush – complete with our famous workmanship guarantee?

We’re also Adelaide’s favourite hot water specialists for repairs, replacements and installations – so protect your hot water system by trusting the friendly Adelaide plumbing team. We can’t wait for your call.