Electric storage hot water systems are still one of the most common setups in Australian homes. But while they might look the same as they always have, there have been major improvements — in performance, energy efficiency, and safety.
If your system’s older or you’re not sure what you’ve got, this guide breaks down how these systems work, what’s changed over time, and why choosing a qualified plumber makes a real difference to your running costs and reliability.
What Is an Electric Hot Water System?
An electric storage system heats cold water using one or two electric elements inside an insulated tank. It stores that heated water until you need it — for a shower, laundry, or dishes.
How It Works
- Cold water enters the tank
- A heating element near the bottom switches on via thermostat
- Water heats to a set temperature (usually 60–70°C)
- Hot water rises to the top of the tank
- Hot outlet delivers to taps
- Pressure relief and tempering valves manage safety and temperature
- A sacrificial anode helps prevent rust inside the tank
It either heats constantly or is timed to run during cheaper off-peak hours — depending on how it’s installed.
Why Older Electric Systems Cost You More
Many people assume all electric systems are the same. They’re not. Older or cheaper models still in use today often:
- Lose heat quickly due to poor insulation
- Only have a single heating element, meaning slow recovery after showers
- Lack precise thermostat control, causing water to overheat
- Aren’t optimised for off-peak usage or solar
- May not include tempering valves, which are now mandatory for safety
If you’ve got one of these older units — or if it’s been 10+ years since your last install — chances are you’re wasting money without realising it.
What Makes Modern Electric Systems Better?
New-generation systems have solved most of the above problems. Here’s what you’ll get today:
- Improved tank insulation to hold heat longer
- Dual-element systems for faster recovery
- Smart thermostats to better control water temperature and power usage
- Solar PV compatibility — heat water for free when the sun’s out
- Tempering valves to regulate outlet temperature for safety
- Compact units with longer warranties and corrosion protection
Modern systems not only cost less to run — they’re also safer and more consistent.
Common Issues (And When to Call a Plumber)
Even newer systems can develop issues, especially with heavy use or hard water. Watch for:
- Water not staying hot
- Higher power bills with no change in usage
- Water leaking around the base or from valves
- Rust-coloured water or sediment buildup
- Bubbling or banging sounds inside the tank
These are signs of scale, element failure, thermostat issues, or tank corrosion — and they usually get worse (and more expensive) the longer they’re ignored.
Why You Need a Qualified Plumber
Replacing or installing an electric system requires careful setup. A licensed plumber ensures:
- Safe and compliant installation
- Proper temperature settings and valve compliance
- Correct sizing and tariff alignment
- Long-term performance and warranty protection
At RJT Plumbing and Gas, we make sure your system isn’t just working — it’s working smart.
Looking for a New System?
If you’re exploring your options, check out our breakdowns of the most popular alternatives:
- Gas Storage Hot Water Systems
- Continuous Flow (Tankless) Systems
- Heat Pump Hot Water Systems
- Solar Hot Water Systems
We’ll help you understand the pros, cons, and ideal setups for each — so you can make the right choice.
Book a System Check or Upgrade Quote
If your hot water system is older than 8–10 years, or you’re unsure how efficient it is, now’s the time to act. We’ll assess your current setup, check your energy alignment, and recommend options to reduce your bills and improve performance — no pressure, just facts.
→ Call RJT Plumbing & Gas today for a system check in North Lakes and surrounds.
