Why Is My Gas Hot Water System Not Working? (And What Can I Do About It?)

Why has my hot water suddenly stopped working?

If your gas hot water system has stopped producing hot water, it's usually due to one of a few common issues: the pilot light has gone out, the gas supply has been turned off, the thermostat needs adjusting, or there's a fault with the system that requires professional repair.

The good news? There are a few things you can safely check yourself before calling a tradie. The bad news? Gas systems aren't something you want to DIY beyond basic checks—they combine flammable gas, high temperatures, and water pressure, so safety has to come first.

What can I safely check myself before calling a plumber?

Before you pick up the phone, here's what you can look at:

1. Check the pilot light (older systems only)
If you have an older gas hot water system, the pilot light may have simply gone out. You'll usually find instructions on the unit itself, but the general process is:

• Turn off the gas supply and wait a few minutes for any residual gas to clear

• Turn the gas control knob to "pilot" and hold it down

• Use the igniter button or a long lighter to relight the flame

• Once lit, hold the knob for about 30 seconds, then release

If it won't stay lit after a couple of attempts, stop and call a professional.

2. Check the gas supply valve
Look for the valve on the gas line leading to your hot water system. If the handle is parallel to the pipe, it's open. If it's perpendicular (at a 90-degree angle), it's been turned off—flip it back.

3. Adjust the thermostat
If the water is too hot or too cold, your thermostat might need tweaking. Most systems have a dial or screw near the bottom of the tank. The ideal temperature is:

• 49°C for instantaneous systems

• 60°C for storage tank systems

Important: If you smell gas at any point, stop immediately. Turn off the gas supply, open windows for ventilation, and call a licensed gas fitter straight away.

When should I call a professional instead of trying to fix it myself?

You should call a licensed gas fitter if:

• The pilot light won't stay lit after a couple of tries

• There's a significant water leak around the system

• You can smell gas (even faintly) and it doesn't go away

• The system is making unusual noises that persist after flushing

• You feel uncomfortable or uncertain about any step

Australian law is very clear: only licensed professionals can legally work on gas systems. DIY gas work can lead to fires, explosions, carbon monoxide poisoning, voided insurance, and hefty fines. It's not worth the risk.

Why is professional repair worth the cost?

Nobody wants an unexpected repair bill, but professional service actually saves you money in the long run. Here's why:

• They fix the root cause, not just the symptom. That weird noise might seem minor, but it could indicate a bigger issue that'll leave you cold again in a few weeks if ignored.

• Your system lasts longer. With proper maintenance, a gas hot water system can last 20+ years instead of the typical 8–12 years.

• Energy savings add up. A properly maintained system runs more efficiently, lowering your gas bills.

• You stay compliant and insured. Professional work comes with compliance certificates and warranties that keep your insurance valid.

Who should I call for gas hot water repairs in Melbourne?

The team at Good Maintenance has fully licensed, registered, and experienced plumbers who are certified in Type A gas fitting—meaning they're qualified to repair and maintain gas hot water systems to Australian safety standards.

We'll diagnose the real problem, fix it properly, and make sure your system is safe and efficient. Plus, our work is backed by warranties and compliance certificates for your peace of mind.

Let's get your hot showers back. Contact Good Maintenance today.

Key takeaways:

• Check the pilot light, gas valve, and thermostat before calling

• If you smell gas or feel uncertain, stop and call a pro immediately

• DIY gas work is illegal and dangerous—leave it to licensed tradies

• Professional maintenance extends your system's life and saves you money