Where to find it
Look for the biggest grille in the house, usually central in the hallway. On a ceiling grille, the frame often hinges down or lifts out and the filter sits behind it. Floor return grilles in older homes may have a filter pad underneath or nothing at all. If there's no filter at the grille, it may be in the heater cabinet in the roof space, under the floor or outside, and that one is best left for the service.
How often to clean it
Check it at the start of winter and every few weeks while the heating is working hard, more often with pets or building work. Switch the heater off at the controller first. Vacuum a dry filter or wash a washable one as the manual says, and let it dry completely before it goes back. A clogged filter starves the heater of air, which can make it overheat and cut out, and the fan works harder.
Keep furniture, rugs and curtains clear of the return grille and the outlets too. A blocked return does the same damage as a dirty filter.
What a gasfitter's service covers instead
Cleaning the filter is housekeeping, not a service. Energy Safe Victoria recommends servicing ducted gas heaters every two years, with a carbon monoxide test at the outlets in every room. Its list for a gas appliance service covers a visual inspection of the appliance and flue, a negative pressure and combustion spillage test, internal cleaning, repair or replacement of parts, and a test run. That work needs a licensed Type A gasfitter.
Our team looks after the electrical side, such as the power supply, controller and wiring. Duct cleaning is a separate job again.
What you can safely do now
- Turn the heater off at the controller before opening the return air grille.
- Vacuum or wash the filter as the manual describes, and let it dry fully.
- Keep the return grille and outlets clear of furniture, rugs and curtains.
- Leave the heater's panels, burner and flue alone; that's gasfitter work.
Services that can help
Read more in our guides
Related questions
- Why do my heating ducts tick or bang when the heater starts?Light ticking, or a single soft pop as the heating starts or stops, is usually metal parts warming and expanding: the heater's plenum, the return air box, duct collars…
- Why does my heater smell when I turn it on for the first time in winter?A dusty, slightly burnt smell on the first run of the season is usually dust burning off the heat exchanger, coil or element, and it fades.
- Why has one zone stopped working on my ducted system?When one zone gets no air but the rest work, check the controller first: the zone may be switched off, on a schedule or, with temperature-controlled zones, already at…
- My gas heater flame looks different. Is that a problem?Yes, treat it as one.
Sources for this answer
2 sources, with the date each was checked
- 1.Energy Safe Victoria: It is recommended that ducted heaters are serviced every two years and during this service a CO test should be conducted at the heating vent outlets in all rooms. Accessed 30 September 2026.
- 2.Energy Safe Victoria: Type A appliances include domestic and light commercial type appliances such cookers, space heaters, central heaters, water heaters, catering equipment and leisure appliances. So, when looking to service and repair your… Accessed 30 September 2026.
General information for homes in Victoria. Every installation is different, so treat this as a starting point. Where this answer refers to Victorian safety or rental rules, the sources above have the current requirements.