Cooker Safety Checker
Safety Assessment
Answer these 5 questions to identify potential risks. Based on New Zealand gas safety standards.
Imagine this: you’re making dinner, the kitchen smells like roast chicken and garlic, and then-boom. A cooker bursts. Not a small pop. A full-on rupture that sends flames, shards of metal, and smoke across the room. It’s rare, but when it happens, it’s terrifying. And it’s almost always preventable.
Gas Build-Up Is the #1 Culprit
Most cooker bursts happen because gas isn’t burning properly. If the burner flame goes out but the gas valve keeps leaking, gas fills the oven cavity. When you turn it back on-or when a spark from the igniter fires-it doesn’t just light the burner. It lights the whole pocket of gas. That’s an explosion.This isn’t science fiction. In 2023, New Zealand’s Consumer Protection Agency documented 17 cooker-related incidents in the past year, and 12 of them were traced to gas leaks after flame failure. Older models, especially those without flame failure devices (FFDs), are far more dangerous. If your cooker is over 15 years old and doesn’t shut off gas when the flame dies, it’s ticking time bomb.
Blocked Burner Ports or Dirty Jets
Grease, food splatter, and even spider webs can clog the tiny holes in burner ports. When this happens, gas doesn’t flow evenly. Instead of a steady blue flame, you get yellow flickers, uneven heating, and-worse-gas escaping sideways into the oven cavity.One homeowner in Christchurch had her cooker burst after a spider built a nest inside the burner jet. The gas couldn’t escape properly, pooled in the oven, and ignited when she turned it on. She didn’t even notice the smell because the leak was slow and constant. By the time she smelled gas, it was too late.
Dirty jets don’t just cause explosions. They also make your cooker use 30% more gas. That’s not just dangerous-it’s expensive.
Faulty or Missing Flame Failure Devices
A flame failure device (FFD) is a simple safety switch. It’s usually a thermocouple or ionisation probe near the burner. If the flame goes out, it cuts the gas supply within seconds. Modern cookers have them built in. But many older models-especially imported second-hand units-don’t.In 2024, a study by the New Zealand Gas Industry Safety Group found that 42% of cookers over 20 years old had no working FFD. Some had been removed by DIYers who thought it was ‘just a wire’. Others were never installed. If you bought your cooker second-hand from a garage sale or online marketplace, there’s a high chance it lacks this critical safety feature.
Overheating Due to Poor Ventilation
Cookers need airflow. If you’ve shoved yours into a tight cabinet, covered the vents with towels, or packed it with pots and pans so tightly that air can’t circulate, heat builds up. That heat doesn’t just make the oven too hot-it can warp metal parts, melt plastic seals, and cause gas valves to stick open.One Wellington family had their cooker rupture after they used it daily for a week while renovating the kitchen. They’d blocked the rear ventilation panel with insulation foam, thinking it would help with heat retention. The oven reached 220°C internally. The gas valve housing softened, leaked, and ignited. The fire department said it was a textbook case of heat trapping.
Using the Wrong Gas Type
New Zealand uses liquefied petroleum gas (LPG) in most homes, especially rural areas. But some imported cookers are designed for natural gas (methane). The pressure, jet size, and burner design are completely different.Installing a natural gas cooker on an LPG line without proper conversion is like putting diesel in a petrol engine. The gas flows too fast. Too much gas enters the burner. It doesn’t burn cleanly. It pools. And when it ignites, it doesn’t just light-it detonates.
There were 9 confirmed cases of this in New Zealand in 2025. All involved imported cookers bought online. None had been professionally converted. All resulted in partial or full cooker failure.
Physical Damage or Corrosion
A cooker isn’t just a box with burners. It’s a system of pipes, valves, seals, and metal chambers. If the gas line is bent, cracked, or rusted, it can leak. If the oven door seal is torn, gas can escape into the cavity. If the control knob is loose and turns past the ‘off’ position, gas keeps flowing.Corrosion is worse in coastal areas like Wellington. Salt air eats through metal fittings. A valve that should last 20 years might fail in 8 if it’s exposed to damp, salty air and never cleaned. One technician in Porirua replaced 11 gas valves in a single month-all from homes near the beach. The cookers weren’t old. They were just exposed.
What You Can Do Right Now
- Check for an FFD. Turn off the gas, light the burner, then blow it out. If the gas shuts off within 5 seconds, you have a working FFD. If it keeps hissing, get it fixed.
- Clean your burners. Use a toothbrush and warm soapy water every 3 months. Don’t poke with metal pins-use a soft brush or compressed air.
- Never block vents. Leave at least 5 cm of space around the cooker. Don’t store pots on top of it if it’s a built-in model.
- Know your gas type. Check the label on the back. If it says ‘Natural Gas’ and you’re on LPG, don’t use it unless a licensed gasfitter has converted it.
- Replace old cookers. If yours is over 20 years old, consider upgrading. Modern cookers have multiple safety layers: FFD, overheat sensors, gas shutoff valves, and automatic ignition.
When to Call a Professional
If you smell gas, don’t turn on lights. Don’t flick switches. Don’t use your phone. Open windows. Turn off the gas at the main valve. Leave the house. Call the gas company or a licensed gasfitter immediately.Don’t try to fix a leaking valve yourself. Gas fittings require special tools and certification. In New Zealand, only a registered gasfitter can legally work on gas appliances. DIY repairs are illegal-and deadly.
What to Look for in a Repair Technician
- They must be registered with the Gas Safe Register (or New Zealand’s equivalent, Gas Safe NZ).
- They carry a photo ID card with a unique registration number.
- They provide a written safety certificate after work.
- They test for gas leaks with a manometer, not just by smell.
Ask for their registration number. Look it up on the Gas Safe NZ website. If they can’t provide it, walk away.
How Often Should You Service Your Cooker?
Every 2 years for most homes. Every year if you live near the coast, use your cooker daily, or have hard water (mineral buildup can affect valves). If you’ve moved into a new home and the cooker is already installed, get it checked before you light it for the first time.Many people think, ‘It still works, so it’s fine.’ But a cooker that works is not the same as a cooker that’s safe. The worst failures happen when everything seems normal-until it isn’t.
Final Warning
A cooker burst isn’t an accident. It’s a symptom of neglect. It doesn’t happen because of bad luck. It happens because someone ignored the warning signs: a lazy flame, a gas smell, a loose knob, an old appliance.You don’t need to spend thousands to stay safe. You just need to check. Clean. Test. Replace when needed. And never, ever ignore the smell of gas.
Can a cooker explode from just turning it on?
Yes-if gas has leaked and built up inside the oven while the flame was off. Turning it on triggers a spark that ignites the pooled gas. This is why flame failure devices are critical: they stop the gas flow if the flame goes out.
Is it safe to use a second-hand cooker?
Only if it’s been inspected and certified by a licensed gasfitter. Many imported second-hand cookers lack safety features, use the wrong gas type, or have corroded parts. Never plug one in without a professional check.
How do I know if my cooker has a flame failure device?
Light the burner, then blow it out. If the gas stops hissing within 5 seconds, it has a working FFD. If gas keeps flowing, it doesn’t. You can also check the manual or look for a thin metal rod near the burner-it’s the thermocouple.
Can I clean the burner jets myself?
Yes, but carefully. Turn off the gas. Remove the burner caps and soak them in warm soapy water. Use a soft brush or toothbrush to clean the holes. Never use metal pins-they can widen the jets and cause leaks. Dry completely before reassembling.
What should I do if I smell gas near my cooker?
Don’t turn on lights, use phones, or create sparks. Open windows. Turn off the gas at the main valve. Leave the house. Call your gas supplier or emergency services from outside. Never try to find the leak yourself.
If you’ve had a cooker for more than a decade, the safest move isn’t to fix it-it’s to replace it. Modern cookers cost less than you think, and they come with safety systems that older models simply don’t have. Your family’s safety isn’t worth gambling on an old appliance.