Do You Need a Gas Engineer to Replace a Gas Hob?

Replacing a gas hob might seem like a simple swap - unscrew the old one, slide in the new one, and turn the gas back on. But if you’ve ever seen a gas leak or heard the hiss of escaping gas, you know this isn’t a DIY job you can risk. In New Zealand, gas hob replacement isn’t just about convenience - it’s a legal and safety requirement. You need a registered gas engineer. Not a handyman. Not a plumber who does a bit of gas work. A certified gas engineer.

Why You Can’t Do It Yourself

Gas hobs connect directly to your home’s gas supply line. That line carries natural gas under pressure. One wrong turn of a spanner, one loose fitting, one missing seal, and you’re risking a leak. Gas leaks don’t always smell like rotten eggs - the odorant can fade, especially in older pipes. A small leak can build up unnoticed, then ignite from a spark, a light switch, or even static electricity. The result? An explosion. Or worse - carbon monoxide poisoning, which kills silently.

In Auckland, WorkSafe New Zealand enforces the Gas (Safety) Regulations 2010. These rules say clearly: only a licensed gas fitter can install, modify, or repair gas appliances. That includes hobs. Even if you’re just replacing a hob with the exact same model, you still need a gas engineer. The law doesn’t make exceptions for "it’s the same size" or "I’m just swapping it out."

What a Gas Engineer Actually Does

A registered gas engineer doesn’t just screw in the new hob. They do a full safety check before, during, and after the job. Here’s what’s involved:

• Shutting off the gas supply and depressurizing the line
• Inspecting the gas pipe for corrosion, wear, or damage
• Checking the gas pressure with a manometer to ensure it’s within 2 kPa ± 0.5 kPa
• Installing the new hob with correct gas-rated fittings and flexible hoses rated for 2 kPa
• Performing a leak test using soapy water or a gas detector - no shortcuts
• Testing the flame color and height on all burners - blue flame only, no yellow tips
• Verifying ventilation around the hob meets minimum clearance rules
• Providing a Gas Installation Certificate (Form 12) - this is legally required

That certificate isn’t just paperwork. It’s proof your gas system is safe. If you ever sell your house, the buyer’s solicitor will ask for it. If there’s a fire and you didn’t have it, your insurance might deny the claim. And if WorkSafe finds out you did the work yourself, you could be fined up to $5,000 for individuals - or $20,000 for companies.

What Happens If You Skip the Gas Engineer?

Some people think they’re saving money by doing it themselves. They’re not. Here’s what really happens:

• You risk a gas leak - and the cost of repairing damage from an explosion can run into tens of thousands
• You void your appliance warranty - manufacturers require professional installation
• You invalidate your home insurance - most policies require gas work to be done by licensed professionals
• You expose your family to carbon monoxide - an odorless, colorless gas that causes headaches, dizziness, and death
• You get caught - WorkSafe does random inspections and responds to complaints

One real case from Wellington in 2024 involved a homeowner who replaced their hob without a certificate. Three months later, their daughter had chronic headaches. A gas test found a slow leak. The repair cost $1,800. The medical bills? $4,200. The insurance company refused to pay because there was no Form 12. The homeowner paid out of pocket - and got a $2,500 fine from WorkSafe.

How to Find a Registered Gas Engineer

Not all plumbers are gas engineers. Not all electricians are either. You need someone registered with the Gas Register - New Zealand’s official database of licensed gas fitters.

Here’s how to find one:

1. Go to www.gasregister.co.nz
2. Search by your suburb (e.g., "Auckland Central")
3. Filter for "Gas Fitter - Domestic"
4. Check their license status - it must be "Current"
5. Look for reviews mentioning hob replacements specifically
6. Call and ask: "Do you provide a Form 12?" If they hesitate, move on

Most registered gas engineers charge between $250 and $450 for a hob replacement, depending on complexity. That includes the certificate. Compare that to the cost of a hospital visit or a blown-up kitchen - it’s not expensive. It’s essential.

What About Electric Hobs?

If you’re considering switching from gas to electric, that’s a different story. Electric hobs don’t need a gas engineer. But they do need a registered electrician. The wiring must handle the load - usually 3.6 kW to 7.4 kW. Your existing circuit might not be enough. A sparky will check your fuse box, upgrade the circuit if needed, and certify the work under the Electrical (Safety) Regulations 2022.

So if you’re replacing your hob and thinking of switching fuel types, plan ahead. Gas to electric? Call an electrician. Electric to gas? Call a gas engineer. Don’t mix them up.

What to Look for in a New Gas Hob

When choosing a new hob, don’t just pick the cheapest one. Check these:

• Gas type - must match your supply (natural gas or LPG). Most Auckland homes use natural gas
• Gas pressure rating - should be 2 kPa for New Zealand standards
• Clearance from walls and cabinets - minimum 50mm on each side, 600mm above
• Flame failure device - every hob sold in NZ must have this. It shuts off gas if the flame goes out
• CE or NZ mark - proof it meets safety standards

Brands like Smeg, Bosch, and Zanussi are common. But even the best brand won’t save you if it’s installed wrong. Always get it done by a pro.

What to Do If You Already Replaced It Yourself

If you’ve already swapped the hob without a gas engineer - stop. Don’t use it. Turn off the gas at the main valve. Call a registered gas engineer immediately. They can inspect the installation, test for leaks, and issue a Form 12 if everything’s safe. If there’s damage, they’ll fix it. It’s better to pay for an inspection now than risk a disaster later.

Many engineers offer emergency callouts. Don’t wait until you smell gas. If you’ve got a gas hob and no certificate, you’re already in violation. Fix it before it fixes you.

Final Thought: Safety Isn’t Optional

Gas isn’t like electricity. You can’t see it. You can’t hear it unless it’s leaking badly. And when it goes wrong, it goes wrong fast. Replacing a gas hob isn’t a home improvement project. It’s a safety-critical task. The law requires a gas engineer for a reason. And that reason is people - your family, your neighbors, your kids.

Don’t gamble with gas. Hire a licensed gas engineer. Get the certificate. Breathe easy.