Why Your Hot Water Pilot Light Keeps Going Out (and How to Fix It)

Few things are as frustrating as losing hot water. If you have a gas hot water heater, a common culprit is an extinguished pilot light. In this guide, we’ll explain why pilot lights go out and how to fix them, with tips tailored specifically to Brisbane conditions and the types of gas units found in Australian homes.

Important Safety Information:

In Queensland, if you are supervising or performing gasfitting work, you must hold a gasfitting occupational licence. This includes installing, commissioning, maintaining, testing, altering, repairing and servicing a gas system in any building. Gas appliances can be dangerous if mishandled. Gas water heaters should only be operated by individuals with suitable experience, knowledge, and capability. Always refer to your owner’s manual and strictly follow the manufacturer’s instructions when relighting pilot lights or performing gas-related tasks.

What kind of hot water systems have pilot lights?

In Australia, pilot lights are most commonly found in gas storage water heaters, which store and heat large quantities of water. Some instant gas hot water units also use pilot lights, though they’re becoming less common.

Note: Gas continuous flow, electric, heat pump, and solar units do not have pilot lights. If you’re experiencing hot water issues with these units, ensure your power supply is active and contact a hot water specialist.

What is a Pilot Light?

A pilot light is a small flame inside gas hot water systems that stays constantly lit. It ignites a larger burner flame that heats the water when the temperature drops below a certain level. Not every hot water system has a pilot light, though—electric, solar, heat pump, and newer gas continuous flow systems use different ignition methods.

5 Common Reasons Your Pilot Light Keeps Going Out

1. Gas Supply Issues

If the hot water system’s gas supply is not sufficient or is interrupted this can cause your pilot light to extinguish.

How to fix:

• For LPG, check the gas bottles aren’t empty. If you have a manual changeover regulator, switch to the reserve bottle.
• If you have natural (town) gas, ensure the gas meter valve is in the open position.
• Check that the gas valve at the hot water system is in the on position.
• Relight the hot water system following the manufacturer’s instructions.
• If these steps fail, contact a licenced gas fitter.

Example: When LPG bottles are exchanged or refilled, the supply may be temporarily interrupted. Your delivery person might not relight your system, depending on supplier policy and unit accessibility.

3. Gas Supply Issues.
Solution: Check your bottles are full or the valves on Gas Meter the hot water unit are in the on position.

What the next steps after relighting the Pilot light:

• Follow manufacturer instructions to set the gas control valve to the main burner setting.
• For Rheem units, a setting of ‘6’ usually maintains water at about 60°C. Avoid the highest setting, as it may reduce efficiency.
• Secure the front cover properly.
• If issues continue, seek assistance from a hot water specialist.

When to Call the Experts

While relighting a pilot flame can be straightforward, underlying issues (like a faulty thermocouple or gas valve) require professional diagnosis and repair.

At Conrad Martens Plumbing & Hot Water, our Brisbane plumbing experts are ready to assist you. We’ll promptly diagnose and resolve your hot water issues, ensuring your system runs safely and reliably.