Told a near-new unit needed a wash: dust on the filter
At the first service on a unit barely out of its first year, the crew came back with a chemical wash quote. Coils do foul, but not on that timescale in an ordinary bedroom. Age alone should have made the recommendation worth checking.
By Team Snowflake | Reviewed 25 Jul 2026
Case summary
LG Wall-mounted2 years oldHDBPunggol, Singapore
- Concern
- Paying for chemical washing on units barely two years into service, with no cooling complaint on any of them to justify it.
- Found
- Ordinary dust on the filters and a light haze on the fin face, both cleared by a standard service
- Key check
- Pulled the filters, then checked the fin face under torchlight for colour change and blocked fin gaps, finding neither
- Result
- Scope came down from three chemical washes to one routine service with no parts and no solution used. Cooling was already correct and stayed that way. The wash was deferred until the fins actually ask for it.
What we were told
Cooling had been strong since installation and nothing had gone wrong. At the first booked service the crew rinsed the filters, then said every unit was due for chemical washing. No symptom was described and no fin condition was shown. The quote covered all three rooms.
What we checked
Age sets an expectation before anything is opened. A unit this young, in a bedroom with closed windows, should show dust on the filters and very little past them. We checked that expectation directly rather than assuming it. Filters came out first, then the fin face went under torchlight, then supply air was measured at the vent.
Filters held a normal grey dust mat that rinsed off clean under a tap, with no staining left behind.
Fin faces were still bright metal with clear gaps between fins, and a torch shone straight through the block.
Supply air was properly cold and airflow reached the far wall, so nothing was restricting the coil.
What we found
Nothing was wrong. A chemical wash exists to dissolve deposits that brushing and rinsing cannot lift, and a young unit in a dry bedroom has not had time to build any. What the filters held was ordinary dust, which is what filters are for. Setting a wash by age-in-service rather than by fin condition puts the price before the inspection, and the fins here did not call for one.
What fixed it
We declined the wash and did a standard service instead: filters washed and dried, fin face brushed and vacuumed, drain pan wiped, pipe flushed, condenser rinsed. Total scope stayed inside a routine visit and no solution was used. We noted the point at which a wash would become correct for this unit, which is a darkened fin face or airflow that no longer clears the room.
Outcome
Scope came down from three chemical washes to one routine service with no parts and no solution used. Cooling was already correct and stayed that way. The wash was deferred until the fins actually ask for it.
What this case teaches us
A wash is a finding, not a default add-on
- Chemical washing answers a visible condition on the fins, so ask what was seen before agreeing to it.
- A young unit in a clean room rarely builds the kind of layer that needs solution to shift.
- Cooling that is still strong and airflow that is still full are evidence against a wash, not for one.
Questions this case answers
Is a chemical wash worth it on an aircon that is only a year or two old?
Servicing crew says every unit needs chemical washing, is that normal?
When does a chemical wash actually become necessary?
Can strong cooling be a reason to say no to a wash?
Ready to get started?
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.