A reliable supply of hot water is something most Australian homes take for granted—until suddenly it’s not there. Whether you’re starting your day with a warm shower or washing up after dinner, your water heater plays a crucial role in your daily routine. But have you ever wondered how this essential appliance actually works? Understanding the basics of how a water heater operates can help you troubleshoot issues, especially when you discover that your gas water heater isn’t working.
The Basics of Water Heating Systems
In Australia, the two most common types of water heaters are electric and gas. A gas water heater, in particular, is favoured for its energy efficiency and ability to provide hot water on demand. These systems function by using a burner located at the base of the tank to heat the water stored inside. When you turn on a hot tap, cold water is drawn into the tank, the burner ignites, and the heated water rises to the top of the tank, ready to be delivered to your tap.
On the other hand, continuous flow or tankless models heat water only when needed. They are compact and ideal for homes with limited space. These systems use a powerful burner to quickly heat water as it flows through the unit, without the need for storage.
Components of a Gas Water Heater
To understand why your gas water heater isn’t working, it’s useful to know the main parts of the system. A typical gas water heater includes a gas burner, a thermostat, a pilot light or ignition system, and a temperature and pressure relief valve. The thermostat monitors the water temperature and tells the burner when to heat the water. The pressure relief valve ensures that pressure doesn’t build up excessively within the tank, which could otherwise be dangerous.
The pilot light or electronic ignition system is what initially lights the gas burner. If this part fails, the burner won’t ignite, and you won’t have hot water. It’s often the first place a handyman or plumber will check if a gas water heater isn’t working.
Common Reasons for Gas Water Heater Failures
In many cases, when a gas water heater isn’t working, it boils down to a handful of common causes. A faulty thermostat can lead to water that’s either too hot or too cold. If the pilot light goes out or the ignition system fails, the burner won’t start. Sediment build-up at the bottom of the tank, particularly in hard water areas of Australia, can also affect performance. Additionally, if the gas supply has been interrupted or the valve is closed, the system won’t function.
External factors like power outages or even windy weather can blow out a pilot light, especially in older systems that are not fully sealed. It’s also not uncommon for systems over ten years old to begin showing signs of wear, indicating it might be time for a replacement.
When to Call a Professional
If basic troubleshooting doesn’t resolve the issue, or if you’re unsure how to safely inspect your system, it’s best to call a licensed plumber or gasfitter. Australian safety regulations around gas appliances are strict for good reason. A malfunctioning water heater can be hazardous if not repaired correctly.
Professionals can also inspect for gas leaks, test pressure relief valves, and assess the efficiency of the system. If you find yourself repeatedly dealing with the same issue, a professional assessment might reveal underlying problems that require more than just a quick fix.
Keeping Your Water Heater in Good Shape
To prolong the life of your unit and avoid situations where the gas water heater isn’t working, it’s smart to carry out regular maintenance. This includes checking the pressure valve, flushing the tank annually to remove sediment, and inspecting the burner assembly. These tasks can often be handled by a skilled handyman or plumber during a scheduled service call.
Understanding how your water heater functions not only prepares you for minor issues but also ensures your home stays comfortable all year round. In Australia’s diverse climate, from chilly Hobart winters to the tropical heat of Cairns, a dependable water heater is more than a luxury—it’s a necessity.






