A chemical overhaul takes the whole wall-mounted indoor unit off the wall. It is stripped, every part is chemical washed, then the unit is reassembled and tested. That is the step past a chemical wash, for units that are badly fouled or have not been stripped for years. Prices: 1 unit $200, 2 units $370, 3 units $515, 4 units $640, and $150 per unit from 5 units.
Aircon Chemical Overhaul
| Number of Units | Price | Per Unit |
|---|---|---|
| 1 unit | $200 | $200.00 / unit |
| 2 units | $370 | $185.00 / unit |
| 3 units | $515 | $171.67 / unit |
| 4 units | $640 | $160.00 / unit |
| 5+ units | $150 per unit | |
What's included
- 9-point pre-check included with the booking
- Take the whole wall unit off the wall
- Strip the unit
- Chemical wash every part
- Reassemble the unit and refit it
- Test cooling before we leave
Signs your aircon needs an overhaul, not just a wash
A chemical wash cleans the coil in place and handles most deep-cleaning needs. An overhaul is the right call when the problem is deeper than the coil, or when a wash alone no longer brings the unit back. In Singapore's humidity, units that have run for years without a strip-down often hide grime in places a wash cannot reach.
- The musty smell or weak cooling came back soon after a chemical wash
- The unit is more than 5 years old and has never been overhauled
- Heavy mould or thick grime is visible on the blower wheel or inside the casing
- Cooling has dropped noticeably and a wash made little difference
- Water keeps overflowing despite drainage cleaning (debris deep in the tray)
- You are refreshing a unit before renting out or moving into a property
Chemical overhaul vs chemical wash — the honest difference
Both use cleaning chemicals, but the depth is very different — and being sold an overhaul when a wash would do is a common way to overpay.
A chemical wash (from $135 for 1 unit) leaves the unit on the wall: the roller is dismantled, a water tray and cover go on, chemical goes on the coil and blower, then it is rinsed, the drainage is flushed, and the unit is tested. A chemical overhaul (from $200 for 1 unit) takes the whole wall unit off the wall, strips it, chemical-washes every part, then reassembles and tests it.
Our 9-point pre-check tells you honestly which one your unit actually needs — we will not strip a unit that only needs a wash.
What a full chemical overhaul includes, step by step
- 9-point pre-check to confirm an overhaul is genuinely needed.
- The whole wall unit is taken off the wall, then stripped — blower, drain tray, casing and covers removed.
- Every component is cleaned individually with specialised chemicals, not just rinsed in place.
- The blower wheel is cleaned and re-balanced so airflow and noise return to normal.
- The PCB and electrical parts are inspected and dust-cleared.
- Anti-rust coating is applied to metal components to slow future corrosion.
- The drain tray and pipe are pressure-cleaned and treated.
- Full reassembly, then a 5-point performance test before we leave.
How often should you do a chemical overhaul?
For most homes, every 2 to 3 years is right — with routine 3-monthly servicing and a chemical wash every 6 to 12 months in between. Units that run heavily, sit in dusty environments, or are already 5+ years old benefit from an overhaul sooner.
If a recent chemical wash did not fix weak cooling or a returning smell, that is usually the sign the unit has reached overhaul territory rather than needing another wash.
Chemical overhaul pricing in Singapore
Our chemical overhaul is $200 for 1 unit, $370 for 2, $515 for 3 and $640 for 4 units. A typical 3-bedroom HDB flat with 3 fan coil units is $515; a 4-bedroom with 4 units is $640.
The quoted figure is final. Every overhaul includes the 9-point pre-check, full disassembly and individual component cleaning, anti-rust treatment, and a 90-day workmanship warranty. If we find a part that genuinely needs replacing, we quote it transparently before doing anything.
Will an overhaul make an old aircon work like new?
For units under about 8 years old in sound mechanical condition, an overhaul restores most of the original cooling and airflow — it is the most thorough clean short of replacement. Older units, or those with a tired compressor, will improve clearly but may not fully recover their original specs.
If the pre-check shows the unit is near end-of-life, we will tell you honestly — sometimes a new installation is the smarter spend than overhauling a unit on its way out.
✅ Good for
- Aircon over 5 years old without prior overhaul
- Units with persistent issues despite chemical wash
- Heavy mould infestation or strong odour
- Units showing reduced cooling after chemical wash
- Pre-rental property aircon refresh
Recent chemical overhaul jobs
Frequently asked questions
Chemical wash vs chemical overhaul — which do I need?
How much does a full HDB aircon overhaul cost?
Will chemical overhaul make my aircon work like new?
How long does a chemical overhaul take?
Is a chemical overhaul worth it for an older aircon?
Do you need to remove the unit from the wall?
My aircon still smells after a chemical wash — will an overhaul fix it?
Other aircon services we offer
- Normal Aircon Servicing — $55 for 1 unit
- Aircon Chemical Wash — from $135
- Aircon Repair & Gas Top-Up — from $55 incl. pre-check
- Aircon Installation — from $1,200