Common Ducted Heating Problems in Winter and How to Fix Them

When the Melbourne chill sets in, there’s nothing quite like stepping into a home or workplace warmed by a reliable ducted heating system. Whether you’re using gas ducted heating or reverse cycle ducted systems, one thing’s for certain: when something goes wrong, you feel it fast.

Ducted heating systems are designed to be efficient, effective, and easy to use. But like any hardworking appliance, they also wear down over time. From strange noises to uneven heating and spikes in your energy bill, even the best systems can start to struggle.

In this article, we’ll walk through the most common ducted heating issues, what might be causing them, and how you can get them fixed. If you live in Melbourne and rely on your heating day in and day out, knowing when to arrange a ducted heating service can save you time, money, and a lot of frustration.

Uneven Heating Across Rooms

You set the thermostat, wait a bit, then notice one room is roasting while another is still freezing. Uneven heating is a common problem with ducted systems, especially in larger homes or buildings with multiple zones.

There are a few possible reasons why this may be occurring.

First, if there are any blocked or damaged ducts, this will naturally create a barrier and restrict airflow to certain areas. Leaky ductwork can even let warm air escape before it reaches its intended destination. In other cases, the issue may lie with the thermostat itself. If the sensor isn’t reading the temperature accurately, it won’t tell the system to adjust properly.

If you’ve noticed hot and cold spots throughout your home or business, it’s time to arrange a ducted heater service. A professional can inspect the ductwork, clean out any blockages, test the thermostat, and restore balance to your heating.

A Sudden Spike in Energy Bills

Noticed that your energy bills have crept up recently, even though your heating habits haven’t changed? If it’s unrelated to your overall power consumption, an inefficient ducted heating system could be the reason. Of course, cost-of-living is high and bills may be rising due to factors beyond your control, but a major spike just might be due to faults with the system itself.

We should also note that gas and electric ducted systems naturally come with differing running costs. Here’s a graph from Sustainability Victoria that illustrates this imbalance quite well.

As you can see, gas ducted heating is already the most expensive system to run, and this makes addressing any underlying issues even more important. Unless you want truly alarming energy bills, it’s always worth booking in a ducted gas heating service.

When systems aren’t working as they should, they often have to work harder and longer to reach the desired temperature. This can be put down to dirty filters, duct leaks, faulty thermostats, or ageing components that are no longer performing at their best. In reverse cycle ducted systems, refrigerant issues or airflow problems are often the cause behind a reduction in efficiency.

Malfunctioning Thermostats

It’s helpful to think of the thermostat as the brain of your heating system. If it’s not working properly, nothing else will either. For homes with reverse cycle ducted systems or smart zoning, the thermostat plays an even bigger role in system performance.

Therefore, if your heater is turning on and off at random, struggling to reach the right temperature, or refusing to respond to settings, the thermostat could be the culprit. Best case scenario and the issue is fairly simple. It might just need new batteries or a reset. But in other cases, the thermostat may be misaligned, faulty, or outdated.

During a service, a professional HVAC technician will be able to test the thermostat’s accuracy and wiring, then replace it if needed.

Strange Noises

All heating systems make a bit of noise (especially on startup), but if you start hearing banging, rattling, whistling, or humming that wasn’t there before, it’s almost always a sign something isn’t quite right.

Strange noises could point to loose or broken components in the heater itself. For example, a rattling sound may be occurring because a fan is off balance. Whistling could be caused by air trying to push through a clogged filter or narrow duct. Banging or clunking sounds, on the other hand, might indicate a problem with the burners or blower motor in a gas ducted heating system.

If left unchecked, even issues that seem minor could escalate into major repairs or even safety risks. Getting your system serviced at the first sign of trouble, therefore, is the best way to avoid a breakdown during peak winter months.

Unusual Smells When the Heater Turns On

If you notice strange smells when the heating kicks in, don’t ignore them. A mild dusty smell at the start of the season is normal. It’s usually nothing more than a bit of built-up dust burning off. But persistent or strong odours tend to indicate something more serious.

A musty smell could mean mould is growing inside the ducts or around the system. This is particularly common in systems that haven’t been used in a while. A burning smell might suggest an electrical fault or overheating component. If you smell gas, switch off your heating system immediately and call a professional. Gas leaks are serious and need urgent attention.

Any unusual odours should be checked by a licensed technician. A proper ducted heater servicing will include cleaning, safety checks, and repairs if necessary.

The Heater Won’t Turn On at All

Few things are more frustrating than a heater that refuses to start on a freezing morning. If your ducted heating won’t turn on, there are a few basic things you can check first.

Make sure the thermostat is set correctly and that the batteries (if it’s not hardwired) are still working. Check your circuit breaker to ensure the system hasn’t tripped the power. If you have a gas system, check that the gas supply is connected and the pilot light is on (if your model uses one), but always be very cautious with gas. Your best bet is to call us and we’ll send a licensed gasfitter to check it out properly.

If none of these steps solve the problem, it’s best to book a service. A technician can check for blown fuses, faulty wiring, ignition problems, or any internal faults that are stopping the system from running.

Poor Airflow

Even when the system seems to be running fine, weak or poor airflow from the vents can make it hard to heat your space properly. This issue is often linked to dirty filters, clogged ducts, or problems with the blower fan.

Over time, dust, pet hair, and debris can build up inside your ducts and filters, restricting airflow and reducing efficiency. In commercial settings or larger homes, this can be particularly noticeable in rooms further from the central unit.

Cleaning or replacing the air filter is a simple fix that can make a big difference. But if that doesn’t help, it’s worth arranging a full inspection of your system to identify any underlying issues.

Pilot Light or Ignition Problems in Gas Ducted Heating

Older gas ducted heating systems often rely on a pilot light to ignite the burners. If the pilot light keeps going out or won’t stay lit, you may be dealing with a thermocouple issue, a dirty flame sensor, or a problem with the gas supply.

Newer systems may use electronic ignition instead, but these can also fail if there’s a fault with the circuit board or gas valve. If you’re not getting heat and you’ve ruled out the thermostat, this is another area a qualified technician can check.

Never attempt to fix a gas fault yourself. In Victoria, gas systems and appliances can only be handled by a licensed type A or type B gasfitter.

When Should You Arrange a Ducted Heating Service?

Ideally, your ducted heating should be serviced once a year, preferably before the colder months begin. This will help to ensure that the system is safe, clean, and operating efficiently when you need it most.

Signs it’s time to arrange a service include:

• Uneven heating across rooms
  
• Strange noises or smells
  
• A sudden spike in energy bills
  
• Weak airflow
  
• The system won’t turn on
  
• Thermostat or ignition issues

Regular maintenance doesn’t just solve problems — it helps prevent them. A professional can catch small faults early, clean out your system, test for safety issues, and keep everything running smoothly.

Don’t Wait Until It Breaks: Call in the Experts

If you need to arrange a ducted heating service in Melbourne, make us your first and only call. At Maroondah Air Services, we’ve been keeping homes and businesses cosy for more than 25 years and counting.

When your heater isn’t performing the way it should, it’s tempting to put off repairs. But the longer you wait, the worse it becomes, and the more you end up forking out for repairs. Whether you’ve been dealing with inconsistent heating, odd smells, or a system that just won’t switch on, it’s always best to get it looked at sooner rather than later. Much like a car, when one component fails, it puts the others at risk.

From strange noises to malfunctioning thermostats, we’ve seen it all. So don’t suffer through another cold day. Call us to arrange your next service as soon as possible!