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How to maintain your hot water system and make it last
Maintaining a hot water system means a few simple checks: test the relief valve once or twice a year, have the anode rod inspected about every five years, flush sediment from a tank annually, service continuous flow units per the maker's guide, and insulate exposed pipes. Done regularly, this can add years to the system's life.
A hot water system is easy to forget about right up until the morning it gives you a cold shower. The good news is that a storage tank or continuous flow unit will last a lot longer if it gets a little attention now and then. None of it is complicated, and a couple of the jobs are things a handy homeowner can safely do. The rest is quick work for a licensed plumber.
Test the relief valve
Every storage tank has a pressure and temperature relief valve, the PTR valve, with a small lever on top. Lifting that lever for a second lets water flush through and clears any grit sitting under the seat, which is what stops the valve sticking. Do it once or twice a year. Stand clear, because the water is scalding. If the valve keeps dripping constantly afterwards, or will not seal, it has worn out and needs replacing.
Check the anode rod (the part that saves the tank)
Inside every storage tank is a sacrificial anode, a metal rod that corrodes on purpose so the steel tank does not. Once the anode is used up, the tank itself starts to rust from the inside, and that is usually what kills a hot water system. Terry recommends having the anode checked roughly every five years. If it is worn down, swapping it is far cheaper than a new tank and can add years to the one you already own. It is also the fix for a rotten-egg sulphur smell in the hot water, which is a reaction between the anode and bacteria in the tank.
Checking or replacing an anode means isolating the water and power, so it is a job for a plumber rather than a weekend DIY.
Flush out sediment
Over the years, minerals and grit settle on the bottom of a storage tank. On an electric tank that sediment sits over the element and makes it work harder, and it is what causes that rumbling or kettling noise you sometimes hear. Draining and flushing the tank clears it out, keeps the system efficient and takes load off the element. Once a year is plenty for most homes, and it is worth doing as part of the same visit as the anode check.
Continuous flow units and pipe insulation
Gas continuous flow units do not have a tank to flush, but they still benefit from a service. Over time the burner and heat exchanger can collect dust and scale, and the water filter on the inlet can clog, especially in harder water areas. A service keeps them firing cleanly and running at full flow. Gas work is licensed work, so leave anything involving the burner or gas line to a gas fitter.
One thing that helps every system: lagging the exposed hot water pipes with foam insulation. It is cheap, it holds the heat in on the run from the unit to your taps, and it means less waiting and less waste on cold mornings. That part is genuinely safe to do yourself.
One rule cuts across all of it: anything involving gas, the burner, hard-wired electrical elements or draining a pressurised tank is licensed work for a reason. Get it wrong and you can flood a cupboard, gas up a room or leave a tank without a working safety valve. The valve lever and the pipe lagging are fair game. The rest is a quick annual visit.
Terry services and maintains every type of hot water system across Berala and Western Sydney, and can do the anode check, flush and valve test in one go. Book a service with Terry on 0415 274 542 before summer demand hits.
Frequently asked questions
- How often should a hot water system be serviced?
- A yearly check is ideal for most homes: test the relief valve, flush the tank and look over the system. The anode rod needs inspecting roughly every five years. Continuous flow units should be serviced periodically so the burner and inlet filter stay clean.
- How long does a hot water anode rod last?
- A sacrificial anode usually lasts about five years, though hard water or heavy hot water use can wear it out sooner. Checking it every five years and replacing it when needed is the single best way to stop a storage tank rusting out early.
- Can I flush my own hot water tank?
- You can safely test the relief valve and lag the pipes yourself. Draining and flushing a pressurised tank is better left to a plumber, who can isolate the water and power correctly and check the anode at the same time. Terry can do both in one visit.
- Does maintenance really make a hot water system last longer?
- Yes. A worn anode lets the tank rust from the inside, and sediment makes the element work harder, so both shorten a system's life. Regular checks catch these early. Terry has seen well-maintained tanks last years past the average.
- Why does my hot water smell like rotten eggs?
- A rotten-egg or sulphur smell in your hot water is a reaction between the sacrificial anode and bacteria in the tank. It is usually fixed by flushing the tank and swapping the anode, often for a different type, which is a job for a licensed plumber.
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Terry's been sorting plumbing across Berala and Western Sydney since 1986. Call 0415 274 542 for a straight answer and a fixed price.
NSW Licence L10959 · 40+ years experience