Most people don’t think about a gas heater service until their heater stops working – usually on the coldest morning of winter. That’s the wrong time to find out there’s a problem.
Whether you’ve got a ducted system, a wall furnace, or a gas log fire, understanding the ins and outs of gas heater servicing (and why it’s important) puts you in a much better position before the temperature drops.
Quick Insights
- Gas heaters should be serviced at least every two years by a licensed gasfitter.
- A standard service covers inspection, cleaning, carbon monoxide testing, and safety checks.
- Servicing costs typically range from $150 to $500 in Australia, depending on system type.
- Only a licensed gas fitter can legally service the internal components of a gas heater in Australia.
- Yellow or orange flames, unusual smells, and higher-than-normal gas bills are all signs you need a service now.
Why Gas Heaters Need Servicing
The short answer: carbon monoxide.
Gas heaters work by burning natural gas or LPG to produce heat. When that combustion process works correctly, the by-products (including carbon monoxide) are vented safely outside your home through a flue. When something goes wrong with the burner, heat exchanger, flue, or ventilation, those gases can spill into your living space.
Carbon monoxide is colourless, odourless, and tasteless. You can’t detect it without a monitor, and the symptoms – headaches, nausea, dizziness, fatigue – are easy to mistake for a cold or flu. High levels in the air are very dangerous and can cause people to pass out or die.During 2006–07, 365 cases of carbon monoxide poisoning were recorded in public hospitals across Australia.
Beyond safety, there are practical reasons too. Dirty burners and clogged filters make your heater work harder to reach the same temperature, which pushes up your gas bill. Worn parts that go undetected lead to bigger repairs down the track. A gas heater service catches these things early.
How Often Should You Get a Gas Heater Service?
All types of gas heaters should be serviced at least every 2 years by a licensed gasfitter and tested for carbon monoxide leakage. This includes all central heating units, space heaters, wall units and gas log fires.
That recommendation comes from the Better Health Channel, which is maintained by the Victorian Department of Health.
If your system is older or gets heavy use, annual servicing makes more sense. Unflued gas heaters, which vent combustion products directly into the room, warrant closer attention.
One important note for renters: your rental provider (landlord) must ensure a gas safety check every two years as a legal requirement.
What Happens During a Gas Heater Service?
A gas heater service isn’t just a filter change. A licensed gasfitter systematically works through the system. Here’s what a thorough service covers:
- Visual Inspection: The technician checks for signs of rust, corrosion, heat damage, and anything that looks physically out of place.
- Burner Cleaning and Inspection: Burners accumulate dust and debris over time. Dirty burners produce an uneven or yellow flame instead of a clean blue one, which affects both efficiency and safety.
- Filter Cleaning or Replacement: Blocked filters restrict airflow, causing the system to overheat. Most filters can be cleaned; some need replacing depending on their condition.
- Flue and Ventilation Check: The technician inspects the flue for blockages, damage, and corrosion. A blocked flue is one of the main causes of CO spillage indoors.
- Carbon Monoxide Spillage Test: This is the most critical part. The gasfitter will use a probe to check different parts of the heater and the room it is in to ensure there is no carbon monoxide in the air.
- Negative Pressure Test: Extraction fans and kitchen rangehoods can create negative pressure inside your home, drawing flue gases back indoors instead of out. The negative pressure test is particularly important for open-flued gas heaters in homes where weather sealing or draught proofing has been carried out.
- Gas Pressure and Valve Checks: The technician checks that gas is flowing at the correct pressure and that valves are functioning properly.
- Ignition and Thermostat Testing: The system is run through a full heating cycle to confirm it ignites correctly, reaches the set temperature, and shuts off as it should.
If anything fails during these checks, the technician should explain what’s needed before proceeding with any repairs.
How Service Needs Change by Heater Type
Not all gas heater services are identical. The process varies depending on what type of system you have.
Ducted Gas Heaters
Ducted gas heaters require additional checks that wall units don’t. The ductwork itself needs to be inspected for tears, blockages, and loose connections. The fan assembly and motor are cleaned and lubricated, airflow is measured across the system, and the heat exchanger is checked carefully for cracks. A cracked heat exchanger is a serious issue that can allow combustion gases into your air supply.
Wall Furnaces and Room Heaters
These are more straightforward to access, but carbon monoxide and negative-pressure testing is just as important – arguably more so, since these units operate directly in the living space.
Gas Log Fires
Gas log fires often get overlooked because they look decorative rather than functional. They still need the same burner cleaning, flue inspection, and CO testing as any other gas appliance.
Unflued Portable Gas Heaters
These are the highest-risk category from an indoor air quality perspective. They require more frequent servicing and should never be used in bedrooms or small, poorly ventilated spaces.
Signs Your Gas Heater Needs Service Immediately
Don’t wait for the next scheduled service if you notice any of these:
- Yellow or orange flames instead of a consistent blue flame – this indicates incomplete combustion
- Unusual smells when the heater is running, particularly a sulphur or rotten egg smell (this could indicate a gas leak repair is needed urgently)
- Soot or black marks around the heater or on walls nearby
- Headaches, nausea, or dizziness that seem to improve when you leave the house – this is a potential CO poisoning warning; leave immediately, open windows, and call a licensed gasfitter
- The heater keeps turning itself off or won’t ignite reliably
- Higher-than-usual gas bills without a clear reason
- Reduced heating output
Any of these warrants a call to a licensed gasfitter before using the heater again.
What Happens If the Technician Finds a Problem?
If something’s wrong, a good technician explains it clearly before touching anything. You should receive:
- A description of what was found
- The recommended repair or part replacement
- An upfront quote for the additional work
- An honest assessment of whether the repair is worthwhile vs. replacement, particularly for older systems
In some cases, a fault means the heater can’t be used until it’s fixed. If the issue involves a suspected gas leak, the gasfitter must make the installation safe or isolate the appliance entirely before leaving the premises.
A no-obligation quote for any additional work is standard practice, and you’re entitled to ask for one.
How to Choose the Right Technician
In Australia, only a licensed gasfitter can legally service the internal components of a gas heater. Licensed technicians complete specialised Type A gas appliance servicing training, giving them the necessary credentials to identify safety hazards that untrained people would miss.
When you’re looking for a gasfitter, ask to see their licence before any work starts. A licensed professional will carry a photo ID card listing the types of work they’re qualified to perform. For gas plumbing and gas fitting work, this matters both legally and practically.
Red flags to watch for: technicians who quote extremely low prices for a full service, can’t show a valid licence, or skip the carbon monoxide testing step entirely and find someone with a full license.
Ready to Book a Gas Heater Service on the Sunshine Coast?
Universal Plumbing N Gas offers gas heater servicing across the Sunshine Coast for both residential and commercial properties.
Our licensed gasfitters carry out thorough safety checks, carbon monoxide testing, and honest assessments of your system’s condition, with upfront quotes and no surprise costs.
Get in touch for a free quote before winter arrives.
FAQs
At a minimum, every two years – this is the standard recommendation. For unflued heaters or heavily used systems, annually is better. Always check your manufacturer’s manual for their specific guidance.
Cost varies by system type, age, and your location. As a general guide, servicing fees in Australia typically range from $150 to $500. Ducted systems and older units tend to sit at the higher end of that range. Any repairs or part replacements will be quoted separately.
A thorough gas heater service covers a visual inspection, burner and filter cleaning, flue and ventilation checks, carbon monoxide spillage testing, negative pressure testing, gas pressure and valve checks, and a full operational test. Ducted systems also include ductwork inspection, heat exchanger checks, and airflow measurement.
You can clean external components like vents and filters. But internal servicing – including anything involving gas connections, burners, or carbon monoxide testing – is legally required to be carried out by a licensed gasfitter in Australia. DIY work on internal gas components also voids most manufacturer warranties.
Yellow or orange flames, soot deposits around the unit, unusual smells, a heater that keeps shutting itself off, reduced heating output, or unexplained increases in your gas bill. Any symptoms that could indicate carbon monoxide – headaches, dizziness, or nausea that clear up when you leave the house – should be treated as urgent. Stop using the heater, ventilate the space, and contact a licensed gasfitter immediately.
Disclaimer: The information in this article is provided as a general guide only and does not constitute professional plumbing, gas fitting, or electrical advice. In Australia, plumbing and gas fitting work beyond basic maintenance (such as replacing tap washers) must be carried out by a licensed plumber or gas fitter. Regulations vary by state and territory — always check with your local authority before attempting any work. Unlicensed plumbing or gas work may void your home insurance, result in fines, and pose serious safety risks. If you smell gas, call 1800 GAS LEAK (1800 427 532) immediately. If you are unsure about any step in this guide, please contact a licensed professional.