Relighting a Gas Water Heater Safely

Nothing starts a morning on a bad note like a cold shower. If your gas water heater pilot light has gone out, knowing how to relight a gas water heater safely can save you a lot of grief. Gas storage heaters use a standing pilot you can relight yourself by following the steps on the unit’s label. Continuous flow systems are a different story as they use electronic ignition and need a separate round of checks. This guide covers both, plus the safety rules you can’t skip when dealing with gas appliances in Sydney.

Safety First: When NOT to Relight a Gas Hot Water System

Before you touch anything, read this. Safety beats a quick fix every time.

If you smell gas:

Natural gas and LPG both have a rotten-egg odour added on purpose so you’ll notice a leak. If you catch that smell near your hot water system or anywhere in the house, do the following straight away:

• Don’t light matches, lighters, or flick any switches, no sparks or flames of any kind.
• Get yourself and anyone else out of the area immediately.
• If it’s safe without walking back into the affected space, turn off the gas at the meter or cylinder.
• Open doors and windows to let fresh air in, only if you can do it without re-entering the danger zone.
• Call 000 for a major leak or if anyone is at risk. Then ring your gas supplier’s emergency line and a licensed gasfitter.

Do not remove panels or attempt repairs beyond user controls:

The control knob, pilot button, and igniter are there for homeowner use. Everything else, including burner assemblies, gas valves, and internal components, is off limits. In NSW, all gas work beyond basic user controls must be carried out by a licensed gasfitter who issues a compliance certificate on completion.

If your pilot repeatedly goes out or you see signs of poor combustion:

Soot buildup, yellow or orange flames instead of blue, or a pilot that keeps dying all point to a fault. Stop relighting and call a pro. These symptoms can indicate thermocouple failure, gas valve trouble, or ventilation problems, none of which are safe to ignore. EKORP Plumbing is available 24/7 on 02 8667 5354 for urgent gas issues across Sydney.

Quick Answer: The Standard Pilot Relight Steps (Standing Pilot Systems)

For gas storage heaters with a standing pilot, here’s the basic sequence before we dig into the detail:

• Turn the gas control knob to OFF and wait 5 to 10 minutes for any accumulated gas to clear.
• Turn the knob to PILOT, press and hold it down.
• While holding, use the built-in piezo button or a long lighter to ignite the pilot flame.
• Hold the button down for 30 to 60 seconds so the thermocouple heats up, then release slowly.
• Turn the knob to ON and check for hot water at a tap.

Always follow the specific label printed inside your unit’s front cover. Manufacturer instructions take priority over any generic guide.

Step 1: Identify Your System (So You Follow the Right Method)

The relighting process depends on the type of system you have. Get this right before you do anything else.

Gas Storage Water Heater (Often Has a Pilot Window/Control Knob)

These are the tall cylindrical tanks you’ll find outside or in the garage. They keep a stored volume of water hot using a gas burner. Look for:

• A control knob at the base with settings like OFF, PILOT, and ON or temperature markings.
• A small viewing window where you can see the pilot flame burning.
• A piezo igniter button, usually red or black, sitting next to the control knob.

This type runs a standing pilot continuously. If it goes out, the steps in this guide apply.

Instantaneous/Continuous Flow (Usually Electronic Ignition)

These are the compact wall-mounted units that heat water on demand when you open a tap. They don’t have a standing pilot light. The ignition fires electronically each time hot water is requested. If yours isn’t working, relighting the pilot isn’t what you’re dealing with. Check gas supply, electrical power, flow rate, and any fault code on the display.

Natural Gas vs LPG

Your system runs on either natural gas from the mains or LPG from cylinders. If you’re on LPG and the tank ran dry, swapping the cylinder restores the gas supply. You may still need to go through the relighting process once to purge air from the lines. Requirements can vary by property and authority. We will help you confirm what applies before work begins.

How to Relight a Gas Storage Water Heater Pilot Light (Step-by-Step)

Work through these steps carefully and refer to your unit’s label throughout. These are generic steps; your manufacturer’s instructions always come first.

Step 1: Turn the gas control knob to OFF

Find the control knob at the base of the tank, you may need to open an access panel. Rotate it to the OFF or O position to cut gas to both the burner and pilot.

Step 2: Wait 5 to 10 minutes

This is a non-negotiable step. Any gas that’s built up around the burner needs time to clear before you introduce a spark. Skipping this risks a flash fire. Set a timer and wait the full period.

Step 3: Turn the knob to PILOT and press down

After waiting, rotate the knob to PILOT and press it down firmly. This opens the gas flow to the pilot line. Keep it pressed throughout the ignition process.

Step 4: Ignite the pilot flame

While holding the knob down, press the piezo igniter button. You’ll hear a click and see a spark near the pilot. If your unit doesn’t have a built-in igniter, use a long-reach lighter or match as the manufacturer’s label directs. Look through the viewing window to confirm the pilot flame is burning as a small, steady blue flame.

Step 5: Hold the button for 30 to 60 seconds

Keep holding the button or knob down once the pilot is lit. The thermocouple, which is the safety sensor that detects the pilot flame, needs time to heat up before it will signal the gas valve to stay open. Release too soon and the pilot drops straight out.

Step 6: Release slowly and turn to ON

After the hold period, let the button go slowly. If the pilot stays alight, rotate the control knob to ON or your preferred temperature setting. The main burner will fire up the next time the water temperature falls below the set point. If the pilot goes out again, wait 5 minutes and repeat. After two or three failed attempts, stop and call a licensed gasfitter as there’s likely a fault with the thermocouple or gas valve.

Step 7: Test your hot water

Run a hot tap inside the house and give it 10 to 15 minutes. Water should be hot within that window. If it stays cold, or if you notice strange sounds, smells, or flame colours, turn the system off and get a gasfitter in. Don’t keep trying after repeated failures as that’s a sign something deeper is wrong.

If You Have Continuous Flow (Instantaneous) Gas Hot Water

Continuous flow systems heat water on demand using electronic ignition. There’s no standing pilot to relight. If yours isn’t firing, try these checks before calling anyone:

Check the gas supply:

Make sure the gas isolation valve near the unit is fully open. On LPG, check the cylinder isn’t empty.

Check the power supply:

Many of these units need power for the ignition system and controls. Check the power lead is plugged in and the circuit breaker hasn’t tripped.

Try a reset:

Some models have a reset button or reset sequence in the user manual. A reset can clear fault codes and get the unit going again.

Check for error codes:

Modern units display fault codes on a digital panel. Look up the code in your manual to find out what’s needed. If the issue is beyond these basic checks or the fault code points to an internal problem, it’s time to ring a licensed gasfitter. Continuous flow systems need diagnosis for ignition failures, flow sensor faults, and electronic control issues. EKORP’s team services all major brands and provides compliance certificates for every gas job.

Pilot Light Won’t Stay Lit? Common Causes (and What to Do)

If the pilot lights but goes out the moment you release the button, or dies shortly after, there’s a fault underneath. Here are the usual suspects:

Faulty thermocouple or flame sensor:

The thermocouple detects whether the pilot is burning. If it’s dirty, out of position, or failing, it won’t signal the gas valve to hold open and the pilot shuts off. Cleaning or replacing a thermocouple is a job for a licensed gasfitter.

Dirty or blocked pilot assembly:

Dust, debris, or corrosion can narrow the pilot orifice and cause a weak, unstable flame. Clearing it out requires disassembly and should only be done by a pro.

Airflow or ventilation problems:

Gas appliances need a proper air supply and clear flue to burn safely. A blocked flue or restricted airflow makes the pilot unreliable and can also produce carbon monoxide, which is dangerous. Get a licensed gasfitter onto it straight away.

Gas supply issues:

Low gas pressure, line contamination, or a faulty gas valve can all prevent the pilot from staying lit. diagnosis and repair are needed. If your pilot keeps dying, stop attempting relights and call a gasfitter. Callout charges are confirmed before booking.

When to Call a Licensed Gasfitter in Sydney (Non-Negotiables)

Some situations have no DIY option. Call a licensed gasfitter without delay if:

• You smell gas anywhere near the system or in the home.
• The pilot keeps going out or won’t stay lit after multiple attempts.
• The unit won’t ignite at all after following the correct procedure.
• You can see soot, discolouration, or signs of incomplete combustion around the burner.
• The pilot flame is yellow or orange rather than blue.
• You’re planning any repair, renovation, or change to gas appliances or gas lines.

In NSW, all gasfitting work must be done by licensed professionals. After completing gas work they’re required to issue a Certificate of Compliance confirming the job meets safety standards. Hold onto these certificates for insurance claims, property sales, and building inspections.

FAQs

Why did my pilot light go out?

The most common reasons are a strong draught (especially on outdoor units), a gas supply interruption like running out of LPG or mains work in your street, a failing thermocouple that incorrectly triggers the valve to close, or a blocked pilot orifice. The odd outage from wind is normal. Repeated outages mean there’s a fault that a gasfitter needs to look at.

How long should I wait after turning the gas off before relighting?

Wait at least 5 minutes and aim for 10. That gives any built-up gas around the burner time to disperse. Trying to ignite in a confined space before the gas has cleared risks a flash fire. Don’t rush it.

How long do I hold the pilot button down?

Hold it for 30 to 60 seconds after the pilot lights. The thermocouple needs that time to reach the temperature that keeps the gas valve open. Let go too soon and the pilot dies straight away. Check your model’s label for the exact recommended hold time.

What if I smell gas when trying to relight?

Stop what you’re doing. Don’t attempt the relight, don’t flick switches or create any spark. Get everyone out of the area, shut off the gas at the meter or cylinder if it’s safe to do so without re-entering, open doors and windows from outside, and call 000 if anyone is at risk. Then contact your gas supplier’s emergency line and a licensed gasfitter. Gas leaks aren’t a wait-and-see situation.

Do continuous flow systems have a pilot light?

Most modern continuous flow systems don’t have a standing pilot. They fire electronically when you open a hot tap and the water starts flowing. If yours isn’t producing hot water, the issue is most likely gas supply, power, a flow sensor, or an electronic fault, not a pilot light. Check your manual or call a gasfitter.

Do I need a licensed gasfitter in NSW for gas hot water repairs?

Yes, full stop. NSW law requires all gasfitting work, including repairs, installations, and modifications to gas appliances and lines, to be carried out by licensed professionals. It’s a legal requirement that protects everyone’s safety. Licensed gasfitters must issue a Certificate of Compliance after the job. Requirements can vary by property and authority. We will help you confirm what applies before work begins. Always check a gasfitter’s licence before hiring.

Where can I find model-specific relighting instructions?

Start with the lighting label inside your unit’s front cover or access panel. That’s the most reliable source for your exact model. If it’s faded, check the owner’s manual. No manual? Brands like Rheem, Rinnai, Dux, and Bosch have downloadable guides on their websites. You can also ring the manufacturer’s customer service line or ask a licensed gasfitter.

Need Help Relighting Your Gas Water Heater in Sydney?

If the pilot won’t stay lit, you’re not getting hot water, or anything feels off with your gas system, EKORP Plumbing is ready to help. Emergency arrival times depend on location, traffic and plumber availability. We will give you an estimated arrival window when you call. Callout charges are confirmed before booking. Call us now on 02 8667 5354 and we’ll get your hot water sorted.