Every twelve to eighteen months for most UAE homes. Manufacturer intervals assume temperate use; here the system runs close to continuously for months, and construction dust and fine sand load it far faster.
Bring it forward if you live near active construction, within a few hundred metres of the coast, or have just moved into a newly handed-over property. Post-construction dust sits in ceiling voids and feeds into the return for months.
The clearest signals are dust visible at the grilles when the system starts, a musty smell in the first minutes of cooling, and rooms that never quite reach the set temperature.
Water marks on the ceiling below an FCU are a drainage issue, not a duct issue, and cleaning ducts will not fix them. That is a blocked condensate line and it needs clearing before it damages the ceiling.
Ask for before and after photographs of the same identified runs. Without them there is no way to know whether the whole run was cleaned or only the first metre behind the grille.
Want this handled instead?
Inspection, written scope, photo report on completion. Send us a message and we will confirm an inspection slot, usually the same day.