Dux is one of Australia’s best-known hot water brands, trusted for decades across Brisbane and far beyond. But like any system, even the most reliable units can run into trouble eventually. In our exclusive guide, we offer genuinely helpful Dux hot water systems troubleshooting advice for common issues all across the impressive range – whether you’re dealing with no hot water, a leaking tank, or a stubborn pilot light.
From electric Proflo units to popular continuous flow gas systems and beyond, we’ll walk you through the key checks you can do yourself – and when it’s time to call in the pros at S&J Plumbing and Gasfitting.
1. No hot water? Here’s where to start
It’s frustrating when your hot water suddenly cuts out – but before you panic, there are a few simple things to check on your Dux unit.
First, make sure there’s power (for electric models) or gas (for gas models). It sounds obvious, but tripped circuit breakers and turned-off gas isolation valves are more common than you think.
If you have a storage system, check the water supply. Open a hot tap and run it for at least 30 seconds – sometimes you’re just flushing out cold water sitting in the pipe.
If the water still doesn’t heat up, continue with the Dux hot water system troubleshooting steps below.
2. Electric systems – Proflo series
Dux electric hot water systems are some of the most reliable, but they do have safety components that can occasionally trip. For example, if the system overheats or experiences a fault, the Dux hot water system reset button may activate.
This button is typically found behind the access panel near the thermostat and must only be reset by a licensed electrician or hot water plumber.
If you’re using a Dux Proflo water heater, make sure the unit is filled before switching the power back on. Operating a dry tank can permanently damage the element and void the warranty.
If power is connected but the water is cold, you may need to investigate further using the specific Dux Proflo hot water system troubleshooting steps, found in the manual. These include:
- Checking the over-temperature cut-out
- And testing the heating element.
But, again, these jobs are best left to a professional to repair or replace a hot water system if it’s an older unit.
3. Resetting the thermostat (Proflo models)
The Dux Proflo thermostat reset button is usually integrated with the over-temperature cut-out and can only be reset by removing the front panel and pressing the concealed switch. If your system continues to trip after resetting, it may indicate:
- A faulty thermostat
- A failing element
- Or overheating due to scale build-up.
You might also need to perform a Dux Proflo thermostat adjustment if the water is too hot or not warm enough – although this again requires a qualified technician, as the thermostat is not user-accessible.
Proflo units are typically factory-set between 60°C and 70°C, with 60 being the recommended safe minimum for most households.
4. Gas systems – Continuous flow & prodigy models
For gas hot water models, including the Dux Prodigy pilot light range, the first sign of a problem is usually no hot water at all. This could be due to the pilot light going out or an issue with ignition.
To relight the pilot on a Prodigy system:
- Turn the control knob to the “.” (off) position
- Wait five minutes
- Switch to the “pilot” setting.
- Depress the knob fully and press the igniter button repeatedly.
- Once the pilot lights, hold the knob for 20 seconds before releasing.
- Turn to setting “6” for 60C.
If this process doesn’t work, you may have a deeper fault – such as a failed thermocouple, safety shutoff issue, or gas supply problem. In these cases, you’ll need professional Dux gas hot water systems troubleshooting from a licensed gasfitter in Brisbane.
5. Continuous flow systems & digital error codes
Modern Dux continuous flow units may have a digital controller or LED light that displays error codes. For example:
11 = ignition failure
12 = flame loss
14 = overheat protection
31 = sensor fault
99 = flue or fan issue.
These codes can be reset using the unit’s internal controller – some models allow a manual reset via a small button inside the cover. Refer to your specific model’s manual for reset instructions, or ask us about Dux hot water service and diagnostics if you’re unsure.
6. Leaking systems – What’s normal, what’s not
If you spot water pooling around your tank, don’t panic – just yet. Some water escape is normal – especially around the temperature and pressure relief (TPR) valve. A little dripping during the heating cycle is expected.
However, continuous or heavy leaks may indicate:
- A faulty valve
- Corroded tank
- Or excess system pressure.
These are all serious safety issues and should be investigated immediately. Got a Dux hot water system leaking bucketfuls per day? Call S&J Plumbing right away.
Condensation may also be mistaken for leaking – especially with high-efficiency gas or heat pump units, where small puddles are a normal by-product of operation.
7. Hot water cuts out mid-shower?
This is often a flow rate issue. Continuous flow systems require a minimum flow to stay ignited – if you’ve installed ultra-low flow taps or shower heads, the unit may not register enough water movement to trigger heating.
It’s also possible your hot water system is undersized, especially for larger families. If the tank runs cold halfway through the evening, you may need a system upgrade – or at least a review of your energy provider’s off-peak schedule.
8. Other things that might help
A few more quick fixes that could restore your Dux hot water:
- Try turning off and on the power to reset electronic control boards.
- Check that cold water is available – no flow could mean a closed isolation valve.
- Inspect the PTR valve – lift the easing lever briefly to test water movement.
- For Dux storage tanks, ensure the tank is fully filled before restoring power or gas.
If all else fails, a professional and thorough Dux hot water service will uncover and resolve the issue safely and efficiently.
When to replace instead of repair a Dux
Like any appliance, Dux hot water systems don’t last forever. Most Dux tanks come with a 10-year cylinder warranty, but common replacement signs include:
- Frequent resets or tripped safety devices
- Leaking from welded joints or base
- Rust-coloured water
- Inconsistent temperature
- Constantly running out of hot water.
In these cases, we can recommend a new Dux Proflo water heater for you, or another energy-efficient alternative suited to your household’s size, usage patterns, and budget.
Call Brisbane’s hot water experts today
Whether it’s a quick and easy pilot relight or a full system replacement, S&J Plumbing and Gasfitting are your local specialists for Dux hot water repairs, maintenance, and upgrades. We:
- Service all models
- Carry lots of the right parts with us
- And back it all up with years of experience across Brisbane.
Dux hot water not working? Call the friendly team at S&J Plumbing today for reliable help with your Dux hot water system – fast, affordable, always professional.
Image source: https://www.dux.com.au/