Yes, in most cases you can safely replace the burner caps on your gas hob yourself — it's one of the few gas appliance tasks a homeowner can do without a licensed gasfitter. However, it's important to understand exactly what a burner cap is, what you're allowed to touch, and where the legal line sits in New Zealand.
What Is a Burner Cap?
A burner cap (sometimes called a flame cap or burner crown) is the removable ceramic or cast-iron disc that sits on top of the burner body on your gas hob. It distributes the gas flame evenly around the burner. Burner caps are not connected to the gas supply directly — they simply rest in place and can be lifted off without disturbing any gas fittings or pipework.
Because no gas connections are involved, replacing or repositioning a burner cap is considered routine appliance maintenance, not gasfitting work as defined under the Gas Act 1992.
What You Can Safely Do Yourself
As a homeowner, you can safely:
- Remove and refit burner caps for cleaning or replacement
- Clean burner caps with warm soapy water or a soft brush
- Replace a damaged or cracked burner cap with a correct manufacturer-matched replacement
- Reposition caps that have been put back incorrectly after cleaning
These tasks don't involve disconnecting or modifying any gas pipework, valves, injectors, or ignition wiring — so they fall outside the definition of restricted gasfitting work.
Getting the Right Replacement Cap
This is the most critical step. Burner caps are not universal — using the wrong cap can cause uneven flames, poor combustion, carbon monoxide risks, or damage to your hob.
- Always match the replacement cap to your hob's make, model, and burner size (e.g., small, medium, large, or wok burner)
- Check your hob's manual or the manufacturer's website for the correct part number
- Contact the appliance manufacturer or an authorised spare parts supplier — stores like Bunnings or Mitre 10 may stock some generic parts, but manufacturer-specific parts are usually best sourced through the brand's service agent
- If you can't find the exact part, a licensed gasfitter or appliance technician can help source the correct component
How to Replace a Burner Cap: Step-by-Step
Before you start — safety first:
- Make sure all hob burners are turned off and completely cool
- Do not attempt this while the hob is connected to an ignition source that is active
- Never use excessive force — burner caps should lift off easily
Steps:
- Turn off all burners and allow the hob to cool completely.
- Remove the burner grate (the metal trivet that sits over the burner).
- Lift off the old burner cap — it simply rests on the burner body and should come away with a gentle lift.
- Clean the burner body underneath with a damp cloth, removing any food debris or grease. Make sure the small gas ports (holes) around the burner body are clear — a toothpick or soft brush works well.
- Place the new burner cap squarely onto the burner body, ensuring it sits flat and centred. Most caps have a locating lug or notch to help with alignment.
- Replace the grate and test the burner on a low flame to confirm even ignition and a steady blue flame.
Signs the cap is seated correctly:
- Flame burns evenly all the way around
- Flame is predominantly blue (some orange tips are normal, but large orange or yellow flames suggest misalignment or a blocked port)
- No unusual popping or delayed ignition
What Is Restricted Gasfitting Work?
While burner caps are fine to DIY, many other gas hob tasks are legally restricted and must only be carried out by a gasfitter licensed by the Plumbers, Gasfitters and Drainlayers Board (PGDB). These include:
| Task | Restricted? |
|---|---|
| Replacing burner caps | No — homeowner can do this |
| Cleaning burner ports | No — homeowner can do this |
| Replacing gas injectors/jets | Yes — licensed gasfitter required |
| Connecting or disconnecting gas supply | Yes — licensed gasfitter required |
| Replacing ignition electrodes or wiring | Yes — licensed electrician may also be required |
| Installing or relocating a gas hob | Yes — licensed gasfitter required |
| Repairing gas valves or regulators | Yes — licensed gasfitter required |
Always check with the PGDB if you're unsure whether a task requires a licensed tradesperson.
When to Call a Professional
Call a licensed gasfitter if you notice any of the following:
- A smell of gas near your hob at any time
- Burners that won't ignite or keep going out
- Flames that are consistently yellow or orange after refitting the cap correctly
- A cracked or damaged burner body (not just the cap)
- Any work involving the gas connection, valves, or internal components
Gas leaks are a serious safety hazard. If you ever smell gas, turn off the gas supply at the meter, ventilate the area, and call a licensed gasfitter immediately — do not use any electrical switches or open flames. For guidance on gas safety, WorkSafe NZ has useful resources.
You can find qualified, licensed gasfitters in your area on tradedirectory.co.nz.
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