Replacing an old gas cooktop might look like a straightforward appliance swap, but there is more involved than lifting out the old cooktop and connecting the new one.
In Queensland, installing or replacing a gas appliance is gas work and must be carried out by someone appropriately licensed to perform that work. Queensland defines gas work as including installing, removing, altering, repairing, testing and certifying gas systems associated with gas appliances.
For homeowners around North Lakes, Moreton Bay and Brisbane’s northside, here is what actually needs to be checked when replacing a gas cooktop.
1. The Replacement Must Be Installed by a Licensed Gas Fitter
Even if the new cooktop fits perfectly into the existing benchtop, the gas connection itself isn’t a DIY job.
A licensed gas fitter needs to disconnect the existing appliance, install the replacement and make sure the installation is safe before it is put back into service.
This isn’t just about connecting a hose or pipe. The gas fitter is taking responsibility for the safety of the completed installation.
2. The Existing Gas Installation Needs to Be Checked
One of the biggest misconceptions with gas appliance replacement is that because the old cooktop worked, everything underneath it must automatically be suitable for the new one.
That isn’t necessarily the case.
When replacing a cooktop, we may need to inspect things such as:
- the condition of the existing gas pipework and fittings
- the appliance isolation valve
- the gas connection position
- the regulator where applicable
- the operating pressure
- whether the pipework can adequately supply the appliance
- whether there are any signs of leakage or deterioration
Queensland guidance specifically requires installers to consider gas supply capacity when appliance demand changes, including pipe sizing, gas meter capacity and LPG supply capacity where relevant.
A larger cooktop or a model with higher-output burners can have different gas requirements from the appliance it replaces.
3. Natural Gas and LPG Are Not Interchangeable
Before buying a new cooktop, check what type of gas your property uses.
Most appliances will specify whether they are configured for:
Natural gas, typically supplied through a gas network and meter; or
LPG, typically supplied from cylinders or another LPG system.
Some cooktops can be converted between the two using manufacturer-approved components, but they must be correctly configured for the gas being supplied.
Connecting an appliance configured for the wrong gas type can result in incorrect burner operation and an unsafe installation.
4. The New Cooktop Has to Physically Fit
This sounds obvious, but it causes plenty of problems.
A cooktop advertised as “60 cm” doesn’t necessarily have exactly the same cut-out dimensions as another 60 cm cooktop.
Before purchasing the replacement, check:
Overall appliance dimensions
Will it fit the available bench space?
Benchtop cut-out dimensions
Will the appliance actually drop into the existing opening?
Depth below the benchtop
Is there enough space around drawers, cabinetry or an oven underneath?
Gas connection location
Can the appliance be connected safely and remain accessible?
Sometimes the easiest replacement is choosing a cooktop with dimensions close to the existing unit rather than modifying a stone or laminate benchtop afterwards.
5. Rangehood and Cabinet Clearances Matter
This is one of the important checks people often don’t consider until the gas fitter arrives.
Gas cooking appliances need adequate separation from rangehoods, exhaust fans and combustible materials.
Current AS/NZS 5601.1 guidance generally requires greater clearances for new or substantially renovated kitchen installations than may have applied to older existing kitchens. For replacement appliances in an existing installation, manufacturer requirements also need to be checked and may require a greater clearance.
That means an old cooktop fitting into the same hole does not automatically mean the new cooktop can legally and safely be installed there.
The gas fitter may need to check:
- rangehood height
- overhead cabinetry
- nearby combustible walls
- splashbacks
- side clearances
- the manufacturer’s installation instructions
If the existing installation is unsafe or doesn’t provide the required clearance for the new appliance, additional work may be needed before the replacement can be completed.
6. The Installation Needs to Be Tested
Once the new cooktop is connected, the job isn’t finished.
The gas system and appliance need to be checked to make sure the connection is sound and the appliance is operating correctly.
This can include checking gas tightness, operating pressure, burner ignition and flame operation.
The objective is simple: when we leave, the new cooktop shouldn’t just “work”. It should operate safely as part of the complete gas installation.
7. You Should Receive a Gas Compliance Certificate
After completing gas system installation or alteration work in Queensland, the licensed gas fitter must issue the owner with a Gas System Compliance Certificate certifying that the installation complies with the applicable requirements.
Queensland changed its gas compliance plate requirements in 2025, meaning most installations no longer require the old-style physical compliance plate, but the compliance certificate remains important.
Keep the certificate with your property records.
Does an Electrician Need to Be Involved?
Sometimes.
Many modern gas cooktops still require electricity for electronic ignition and may simply plug into an existing suitable power point.
However, if a new electrical outlet, relocation, hard-wiring or other electrical installation work is required, that work needs to be completed appropriately by an electrical contractor.
The gas and electrical sides of the installation are separate safety systems and both need to be correct.
Before You Buy a Replacement Gas Cooktop
If you want to make the replacement as straightforward as possible, take a few photos before purchasing the appliance.
Photograph:
- the existing cooktop
- the model number if accessible
- the area underneath the cooktop
- the gas connection
- the rangehood and surrounding cabinetry
Also measure the existing benchtop opening if possible.
Sending this information through beforehand can help identify obvious compatibility problems before you’ve bought a cooktop that doesn’t fit.
Need a Gas Cooktop Replaced in North Lakes or Brisbane North?
RJT Plumbing & Gas provides licensed gas fitting services throughout North Lakes, Mango Hill, Griffin, Kallangur, Murrumba Downs, Narangba, Redcliffe and surrounding areas of Moreton Bay and Brisbane’s northside.
Whether you’re replacing a failed cooktop, upgrading during a kitchen renovation or aren’t sure whether a new appliance will work with your existing gas installation, we can inspect the setup and make sure the replacement is completed safely and correctly.
Already bought the cooktop?
Send us the model details and a few photos of your existing installation and we can help work out what will be required before installation day.
Frequently Asked Questions
Do I need a licensed gas fitter to replace a gas cooktop in Queensland?
Yes. Disconnecting, installing and connecting a gas cooktop is gas work and must be carried out by someone appropriately licensed to perform the work.
Can a new gas cooktop simply replace the old one?
Not always. The gas fitter may need to check the existing gas pipework, isolation valve, connection, gas pressure, appliance requirements and installation clearances before the replacement can be completed.
Can I replace a natural gas cooktop with an LPG cooktop?
The appliance must be correctly configured for the type of gas supplied to the property. Some appliances can be converted between natural gas and LPG using manufacturer-approved components, but the conversion and installation must be completed correctly.
Will any 60cm gas cooktop fit an existing 60cm opening?
No. Cooktops marketed as the same nominal size can have different benchtop cut-out dimensions, depths and connection locations. The manufacturer's installation dimensions should be checked before purchasing.
Do rangehood clearances matter when replacing a gas cooktop?
Yes. The new appliance must have suitable clearances from rangehoods, cabinetry, splashbacks and combustible materials in accordance with applicable requirements and the manufacturer's installation instructions.
Does a gas cooktop installation need to be tested?
Yes. Once installed, the gas system and appliance need to be checked to ensure the connection is sound and the cooktop is operating correctly.
Will I receive a gas compliance certificate after replacing a cooktop?
Where gas system installation or alteration work is completed in Queensland, the licensed gas fitter must provide the appropriate Gas System Compliance Certificate for the completed work.
Does an electrician need to install a gas cooktop?
Not necessarily. Many gas cooktops use an existing power point for electronic ignition. If electrical installation work such as adding or relocating a power point is required, an appropriately licensed electrical contractor may also be needed.
