Check the filter before normal use
Switch the system off and inspect the removable filter according to the manufacturer instructions. Clean and dry it fully before reinstalling it.
Compare the deeper visible areas
Look through the accessible opening without dismantling the unit. A filter can collect substantial dust while some material also settles around the coil, fan area, louvres or housing.
Do not blow the dust further
Avoid using compressed air or household sprays inside the head unit. If buildup remains beyond the filter, controlled professional cleaning is the safer next step.
The practical takeaway
After renovation work, reset the filter first and use the visible condition of the system to decide whether deeper cleaning is needed.