If your hot water has gone cold and you have a storage gas hot water cylinder, a blown-out pilot light is often the culprit. Relighting it is something most homeowners can do themselves — but it must be done carefully, following the instructions on your specific unit. If you ever smell gas strongly or feel unsure at any point, stop immediately, ventilate the area, and call a licensed gasfitter.
Before You Start — Safety First
Gas work in New Zealand is tightly regulated. While relighting a pilot light is generally considered a task a homeowner can perform on their own appliance, any repair, alteration, or connection to the gas supply itself is restricted work that must be carried out by a licensed gasfitter registered with the Plumbers, Gasfitters and Drainlayers Board (PGDB).
Before touching anything:
- Sniff for gas. If you can smell gas strongly near the unit or anywhere in the house, do not attempt to relight. Leave the building, leave doors open, and call your gas supplier or 111.
- Make sure the area is well ventilated.
- Keep ignition sources (lighters, matches, cigarettes) away until you are ready to use them at the correct step.
- Have the appliance manual handy if possible — instructions vary between brands and models.
Understanding Your Hot Water System
Not all gas hot water systems have a traditional standing pilot light. Older storage cylinder units (sometimes called a "califont" or "wetback" style) typically do. Many modern continuous flow (instantaneous) units use electronic ignition and do not have a pilot light at all — they ignite automatically when you turn on a tap. If your continuous flow unit isn't working, the issue is more likely a flat battery, a tripped gas valve, or a fault requiring a gasfitter.
Check your unit's label or manual to confirm which type you have before proceeding.
What You'll Need
- A long-reach barbecue lighter or long matches
- Your appliance manual (if available)
- A torch (handy for seeing inside the access panel)
Step-by-Step: Relighting the Pilot Light
These are general steps based on common NZ storage gas hot water units. Always follow the specific instructions printed on your appliance — they take priority.
1. Turn the gas control knob to "Off"
Locate the gas control valve on the unit (usually near the bottom). Turn the knob to the "Off" position. Wait at least 5 minutes to allow any residual gas to disperse before proceeding. This is a critical safety step — do not skip it.
2. Remove the access panel
Most units have a small panel near the base that you can unclip or unscrew to access the burner and pilot assembly.
3. Turn the knob to "Pilot"
Once you've waited the full 5 minutes, turn the control knob to the "Pilot" position.
4. Press and hold the pilot button (or knob)
Press down the pilot button (on some units you press the control knob itself down). This manually opens the gas supply to the pilot tube only.
5. Ignite the pilot
While holding the button down, bring your long lighter or match to the pilot burner tip — a small tube near the main burner. You should see a small blue flame appear.
6. Hold the button for 30–60 seconds
Keep holding the button down after the pilot lights. This heats the thermocouple — a safety sensor that tells the valve the pilot is genuinely lit. If you release too soon, the pilot will go out again.
7. Release and check
Slowly release the button. The pilot flame should stay alight. If it goes out, wait 5 minutes and repeat the process. If it won't stay lit after two or three attempts, the thermocouple may be faulty — call a licensed gasfitter.
8. Turn to your desired temperature setting
Once the pilot is stable, turn the control knob to your preferred temperature setting (commonly marked "Hot" or with a temperature range). Replace the access panel.
Allow an hour or two for a storage cylinder to fully reheat.
Why Does the Pilot Light Keep Going Out?
If your pilot light blows out repeatedly, there may be an underlying issue:
| Possible Cause | What to Do |
|---|---|
| Faulty or worn thermocouple | Call a licensed gasfitter to replace it |
| Draughts near the unit | Check ventilation — do not block required air vents |
| Low gas pressure | Contact your gas supplier |
| Dirty pilot orifice | A gasfitter can clean or replace it |
| Ageing appliance | Consider a replacement unit |
When to Call a Professional
Call a licensed gasfitter (find one via the PGDB register or on tradedirectory.co.nz) if:
- You smell gas at any point
- The pilot won't stay lit after a couple of attempts
- The thermocouple or any gas component needs replacing
- You notice unusual smells, soot marks, or yellow/orange flames (should be blue)
- Your unit is old and you're considering upgrading
Any repair or replacement of gas components — including thermocouples, gas valves, burners, or connections — is restricted work under the Gas Act 1992 and must be done by a gasfitter licensed with the PGDB. Unlicensed gas work is illegal and dangerous.
For guidance on safe and energy-efficient hot water systems in New Zealand, Energywise has useful information on comparing gas, heat pump, and solar options.