What is an Aircon Chemical Overhaul?
Ever switched on your aircon and caught a sour, musty whiff? If it keeps coming back after a normal service, an aircon chemical overhaul is probably the fix.
Since Brian started Cool Earth Aircon in 2007, we’ve opened up plenty of Marine Parade units that looked fine outside and were a mess inside.
A chemical overhaul is the deepest clean an indoor unit can get. We take the unit apart. The fan motor, blower wheel, coil, drain pan and housing are cleaned one by one, checked for wear and put back together, then tested.
Overhaul or wash?
The two jobs often get mixed up. According to Helpling Singapore, a chemical wash usually takes 1 to 2 hours per unit, while an overhaul takes 3 to 5 hours because the unit is dismantled.
| Chemical wash | Chemical overhaul | |
|---|---|---|
| Unit stays on the wall? | Mostly, yes | No, it comes apart |
| Typical time per unit (Helpling) | 1 to 2 hours | 3 to 5 hours |
| Best for | Routine yearly upkeep | Heavy mould, sludge, weak cooling |
When your unit needs one
An overhaul is the right job if your unit has any of these:
- Heavy black mould
- A strong sour smell
- Jelly-like sludge in the drain pan
- Severe loss of cooling
- An age of more than five years, with no deep clean ever done
Marine Terrace, Marine Crescent and Marine Drive flats from the 1970s often need it because of older units and old piping. Property listings on PropertyGuru show many blocks on Marine Crescent and Marine Terrace were built in 1974 and 1975. That’s a lot of years of humid air and condensate running through the same pipes.
What it costs
Overhauls are priced at S$130 to S$180 per unit, with a fixed quote before work and a 90-day workmanship warranty. For a flat with three wall-mounted units, that works out to S$390 to S$540.
For comparison, Helpling puts typical Singapore overhaul prices at S$150 to S$250 per unit. You’ll know the exact figure before we start, so there are no surprises on the day.
If a chemical wash will solve the problem for less, we will tell you first.
Why Older Marine Parade Units Need It
Units that have run for years without a deep clean build up mould and sludge that a surface wash cannot remove. Humidity in Singapore sits above 80% year-round, according to aircons.sg, and the damp inside a running unit gives mould plenty to feed on.
That same guide says a standard wipe-down or general service won’t clear mould that’s embedded in the blower wheel, coil and drain pan. This is why the smell often returns within days of a basic service.
A blocked drain pan is also worth fixing for another reason. A Snowflake Aircon guide on drip trays points out that stagnant condensate in a pan or blocked drain can become a breeding spot for Aedes mosquitoes.
Not sure which job your units need? Tell us what you’re seeing, and we’ll say honestly whether it’s a wash or an overhaul. See the full price list for how overhaul pricing compares with a wash.
