Warning signs your ducted heater is in trouble.
Which signs mean stop using it right now, which mean book a service this month, and which are perfectly normal. Including the carbon monoxide symptoms that read like flu, and the faults we see most across Ballarat’s older housing.
The carbon monoxide signs.
Read this section even if you skip the rest. Four signs matter:
- A yellow or orange lazy flame instead of a crisp blue one. Blue means complete combustion. Yellow means it is not burning properly.
- Soot or black staining around the heater, the flue or the outlets.
- Unusual condensation on the windows when the heater is running.
- Headaches, nausea or dizziness that get better when you leave the house and come back when you return.
That last one is the one that saves people, because carbon monoxide is colourless and odourless and the symptoms read exactly like flu. A household that all feels off through winter and mysteriously fine on holiday is a household with a story worth taking seriously. If any of this is happening: turn the heater off, open the house up, get out, seek medical advice, and do not use the heater again until a licensed gasfitter has carbon monoxide tested it to AS 4575, the standard covering the servicing of domestic gas appliances.
This matters more in Ballarat than in newer suburbs. Energy Safe Victoria, the state gas safety regulator, has issued repeated safety alerts about open-flued heaters, and they land hardest on the pre-1960 housing that makes up a large share of the City of Ballarat established suburbs. The open-flued heaters common across Ballarat East, Soldiers Hill and the established areas draw combustion air from inside the room, and the risk climbs when a home has been draught-proofed or has a rangehood or bathroom fan running, because negative pressure can pull flue gas back down into the living space. A gas smell, or a pilot that keeps blowing out, belongs in this same category. Stop, do not troubleshoot it yourself.
Signs that mean this month, not next winter.
- A bang on startup. That is delayed ignition. Gas pools in the combustion chamber for a moment before it lights, so instead of igniting cleanly it goes off with a thump. Usual causes are dirty or partly blocked burners, or a failing ignition system. Beyond being alarming, repeated delayed ignition stresses the heat exchanger, which is the one component you cannot afford to lose.
- Rising gas bills for the same comfort. That gap between what you pay and what you feel is the clearest efficiency-loss signal there is. The usual suspects are a blocked return-air filter making the fan fight the system, ducts leaking conditioned air into the roof cavity, a unit that has degraded and is no longer burning efficiently, or simply a home with no zoning heating empty bedrooms every evening. In Ballarat this shows up faster than elsewhere because the system runs so many more hours across a long winter, so a small efficiency loss becomes a large bill.
- Longer and longer run times to reach the same setpoint.
- Short cycling, where the unit fires, runs briefly, shuts off and repeats. Often a restricted-airflow problem tripping the overheat cutout.
- New noises. A rumble that was not there before, a squeal that says bearing, a rattle that says something has come loose in the roof.
- Uneven heating, where the back bedrooms never come up.
None of these are emergencies. All of them are cheaper this month than in July. A service with a carbon monoxide test runs $160 to $280 and our service and repair page covers what we actually check, while the timing guide explains why February and March are the months to do it.
What we actually find in Ballarat homes.
After enough winters here, the same faults come around:
- A blocked return-air filter. Genuinely the most common cause of the no-heat callouts we attend, and the one thing you can fix yourself in five minutes. Clean it monthly through winter, not annually.
- Rodent damage in the roof cavity. More common here than people expect. A cold Central Highlands winter pushes rodents into roof spaces looking for exactly the warm insulated thing your ducts are, and chewed duct insulation is a slow leak of the heat you are paying for.
- Ducts adrift or sagging. A duct that has come off its collar is heating your roof cavity beautifully. This is behind most cold-back-bedroom complaints, along with outlets that were never balanced properly at commissioning.
- Overheat cutouts tripping. Almost always restricted airflow, and almost always the filter or a crushed duct rather than the unit itself.
- An undersized unit. Not a fault so much as a defect built in on day one. A heater sized off floor area rather than a room-by-room heat-load calculation is undersized for Ballarat, which sits at roughly 435m in the Central Highlands with frosts from May through September. It runs flat out and never quite gets there. Our choosing an installer guide explains how to catch that before you sign.
Things that are not a fault.
We would rather you did not pay us to attend these. On the first run of the season, a dusty burning smell is usually just that: dust settled on the heat exchanger over a summer of sitting idle, burning off across the first fifteen or twenty minutes. That is expected. What is not normal is a burning smell that persists past that, one that is acrid or electrical rather than dusty, or any burning smell appearing mid-season on a heater that has been running for weeks. Turn it off and call rather than waiting to see if it clears.
Likewise, a system that ticks and pings as ducts expand is normal. A heater that runs longer on a minus two morning than a twelve degree one is normal, that is the unit doing its job. And check the simple things before you call anyone: the isolation switch, the thermostat batteries, and the filter. We have driven to plenty of no-heat jobs that were a tripped switch, and the DIY guide lists what else is genuinely yours to check.
Two cold bedrooms in Delacombe.
A four-bedroom home in Delacombe, eight years old, ducted gas. The complaint was the two rear bedrooms never getting warm while the living area cooked, and a gas bill that had climbed about a third over two winters for no extra comfort. The owner assumed the unit was failing and was expecting a replacement quote.
It was not the unit. In the roof cavity, one duct had pulled off its collar entirely and was pumping heated air straight into the roof space, and a second had rodent damage through the insulation with the inner liner intact but the R-value gone. The unit itself tested fine and the carbon monoxide test was clean. We reconnected and re-supported the first duct, replaced the damaged run, rebalanced all twelve outlets, and fitted mesh at the two roof entry points the rodents were using. $780. Both bedrooms came up to temperature and the following winter’s bills came back down.
The point: the symptom said the heater was dying, and the cause was a $780 duct job. Any installer who quotes a replacement without going into the roof cavity first is guessing. If yours genuinely is at the end, the lifespan guide covers where the repair-or-replace line sits and the pricing page has the numbers.
Where we work.
Something not right with your heater?
Licensed diagnosis, carbon monoxide testing, honest repair-or-replace advice. Free quote.