Headaches or nausea when the heater's on?
Carbon monoxide can come from any gas heater, and Energy Safe Victoria lists dizziness, nausea, headaches, people and pets getting sick at the same time, and feeling unwell only at home as warning signs. If you suspect it, get everyone outside into fresh air, turn off gas appliances and open doors and windows, and call Nurse-on-Call, a doctor or 000 in an emergency. Leave the heater off until a qualified gasfitter has checked it.
How often does a ducted heater need a service?
For gas, the regulators agree. Energy Safe Victoria says at least once every two years by a qualified gasfitter, and Better Health says the same for every type of gas heater. Seeley adds that some of its units may need more frequent service, so read your heater's manual as well.
Ducted reverse cycle is on a shorter cycle. Mitsubishi Electric recommends a professional service once a year, the ACT Government says every year or as the manufacturer recommends, and ActronAir's warranty terms set residential maintenance at once every 12 months.
A carbon monoxide alarm is a good back-up, but Energy Safe Victoria says it should never replace regular servicing.
Servicing and your warranty
Skipping services can cost you cover. ActronAir's terms make the owner responsible for periodic maintenance by a suitably licensed or qualified person, and exclude problems with product serviced by unlicensed people.
Some brands tie longer cover to their own service network. Rinnai's Brivis booklet says its extended warranty of up to 4 years on selected products needs scheduled servicing by Rinnai and online registration in the first 12 months. For Braemar heaters on the 7 year cover, Seeley says the fourth-year service must be done by Seeley International or its nominee.
Common faults, and what they usually mean
Overheating and lockouts. Seeley's technician guide says over-temperature faults are usually caused by restricted airflow, incorrect fan settings, low fan speed or duct restrictions, with a dirty return air filter and too few outlets open among the usual culprits.
Pressure faults. The same guide says most are caused by blocked flues or blocked pressure tappings, which is work for a licensed technician.
A flame that's changed. Better Health lists a yellow or sooty flame, a pilot that goes out or pops and bangs, and soot stains as signs of a faulty heater. Energy Safe Victoria says any change like this needs a gasfitter to inspect it and check for carbon monoxide.
Seeley's guide is blunt about one thing: don't repeatedly reset a heater without identifying the cause of the lockout. Brivis publishes an error codes document for its gas ducted heaters, so note any code the controller shows before you call.
Before you book, check these
The controller
Is it set to heat, at a temperature above the room's, with no timer or schedule holding it off? Write down any error code.
The power
If the controller screen is blank, check the switchboard for a tripped circuit. If it trips again, leave it off and call an electrician or the technician.
The return air filter
Clean or replace it the way your manual says. A clogged one is a common cause of overheating faults.
The outlets
Open them all and move rugs or furniture off floor vents.
Renting in Victoria?
Rental providers must have a gas safety check done every two years by a licensed or registered gasfitter, and from 13 October 2026 that applies to all rental properties with gas. Consumer Affairs Victoria says the gasfitter must be endorsed in Type A Gas Appliances Servicing, shown on their Plumbers Identity Card.
The record should include the gasfitter's name, business details, licence or registration number, the date and the results. A renter can ask for a copy of the latest check in writing, and must get it within 7 days.
What's yours, and what's the gasfitter's
You can
- The controller settings, schedules and batteries.
- Cleaning or replacing the return air filter as the manual says.
- Keeping outlets open and the heater's surrounds clear.
- Booking the service on time and keeping the paperwork.
Leave to a licensed installer
- Opening the heater, the burner and anything on the gas side.
- Checking the flue and testing for carbon monoxide spillage.
- Fan, wiring and control board repairs.
- Any refrigerant work on a ducted reverse cycle system.
What to ask the technician
- Are you a licensed gasfitter, and can I see the licence number?
- Will you check for carbon monoxide spillage as part of the service?
- Will you check the return air filter and the ducts while you're in the roof?
- Is anything you found a safety issue, or just wear?
- Will I get a written record of what you did and found?
- For a rental: are you endorsed for Type A appliance servicing?
What we'd do
What we'd do
We'd book the gas service every two years without waiting for a fault, ask for a carbon monoxide check every time, and keep the record. If the heater starts locking out, we'd stop resetting it and get it looked at. When repairs keep coming back, it's time to read up on replacing a ducted heater. For the service itself, we'd want a gasfitter who works on ducted heaters every week, not one who mostly does hot water.
