Why Does Gas Ducted Heating Make Noise? – How to Fix It

Need help? Call Unitests – Melbourne’s Heating Experts

When your gas ducted heating system starts making unusual noises, it's a clear sign something isn't right.

While a low hum or soft whoosh of air is normal, loud or strange sounds like banging, rattling, or whistling are not.

If you've noticed your heater sounding off lately, it's essential to understand the potential causes and know when to call in professionals like Unitests for an inspection or repair.

Common Noises and What They Might Mean

Banging or Popping Sounds

A loud bang or pop when the heater starts could be due to expanding and contracting ductwork. Over time, as metal ducts heat up or cool down, they can shift slightly, causing a banging noise. However, it can also indicate more serious issues like delayed ignition, which happens when unburnt gas suddenly ignites.

Whistling or High-Pitched Sounds

A high-pitched whistling noise often points to restricted airflow. This can be caused by:

• Dirty or clogged filters

• Blocked vents or ducts

• Closed dampers

Rattling or Vibrating

Rattling sounds might mean there’s a loose panel or screw in the ductwork or heating unit. Alternatively, it could be a sign of a failing fan motor or blower wheel that’s become imbalanced.

Humming or Buzzing

Some humming is expected, but a loud buzz may signal electrical issues, such as a faulty transformer or capacitor. Electrical problems can compromise the efficiency and safety of your heating system.

Booming or Rumbling

A deep rumble or boom could mean the burner is dirty or the heat exchanger is cracked. These are serious issues that can reduce efficiency or, in the worst-case scenario, cause carbon monoxide leaks.

Why You Shouldn’t Ignore Heating System Noises

Unusual noises aren’t just annoying — they’re a warning sign. Ignoring them can lead to:

• Higher energy bills

• Decreased system efficiency

• Costly breakdowns

• Potential safety hazards

Even if the system appears to be working fine, the underlying issue could be developing into a larger (and more expensive) problem.

How Unitests Can Help?

At Unitests, we specialise in diagnosing and repairing all types of gas ducted heating systems across Melbourne. Our licensed technicians have over 30 years of experience and understand the subtle signs of trouble before they become serious.

Here’s what we offer:

• Full system inspections

• Safe and professional repairs

• Regular servicing to prevent issues

• Honest advice on repair vs replacement