Signs Your Ducted Heating Needs a Professional Clean

A few practical signs help indicate when a ducted heating system is genuinely due for a clean, rather than relying purely on a fixed time interval.

A musty or dusty smell when heating first switches on

This is the most common and recognisable sign, a noticeable odour in the first few minutes after switching the system on, which typically fades once accumulated dust has burned off or dispersed, but indicates a build-up worth addressing.

Visible dust around vents

Dust visibly settling around vent covers more than usual, or a fine layer building up near return air grilles, points to more dust circulating through the system than is typical for a recently cleaned setup.

Increased allergy symptoms when heating runs

If allergy-prone household members notice symptoms specifically worsening when the ducted system is in use, that's a reasonably direct indicator of dust or allergens being circulated through the ductwork.

It's been more than a couple of years

Even without obvious symptoms, if it's been longer than 2 to 3 years since the system was last cleaned, that alone is a reasonable trigger to book a clean as preventative maintenance.

After renovations

If you've had renovation work done anywhere in the home, construction dust can find its way into ductwork even with reasonable precautions taken, making a clean afterward a sensible step.