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C Coolbest Aircon
Chemical Wash

Deep Chemical Wash & Overhaul for Singapore Aircon Units

Deep alkaline chemical cleaning for fan coil and condenser units — the fix for clogged, smelly, or under-cooling AC that routine servicing can't resolve.

S$90–180 per unit (chemical wash) — overhaul quoted on inspection
Coolbest Aircon technician performing aircon chemical wash & overhaul in a Singapore home
FROM S$90
18+
Years Experience
10,000+
Units Serviced
4.8★
200+ Google
90
Day Warranty

When A Chemical Wash Is The Right Answer

Routine aircon servicing handles surface dust and a quick drainage flush — but it cannot reach the biofilm and scale build-up caked deep inside the evaporator coil. After 2–3 years of use in Singapore’s humidity, that build-up becomes the main reason your aircon smells musty, leaks water, or stops cooling at its rated BTU capacity.

A chemical wash dismantles the indoor fan coil, soaks the coil and blower wheel in an alkaline chemical reagent, and flushes the drainage line from the inside out. It’s the deepest clean possible without replacing the unit — and it usually restores most mid-life systems to near-factory cooling.

What’s The Difference Between Wash And Overhaul?

  • Non-dismantle chemical wash (S$90/unit): the coil stays mounted, but alkaline solution is sprayed through the fins with catch basins below. Suitable when the unit is fairly recent (under 3 years) and only lightly fouled.
  • Dismantle chemical wash (S$120/unit): the fan coil is removed from the wall, soaked in a dedicated chemical bath for 30–45 minutes, then pressure-rinsed. Standard fix for most 3–7 year old systems.
  • Full chemical overhaul (S$150–180/unit): adds the outdoor condenser — compressor externally cleaned, condenser fins degreased, new insulation applied where needed. Recommended every 3–5 years for units older than 7 years.

All three include a vacuum leak test before reassembly and are covered by our 90-day workmanship warranty.

What The Job Looks Like On-Site

  1. Arrival & prep (~15 minutes): shoe covers on, drop cloth under the unit, and we photograph the pre-wash condition for your records.
  2. Dismantle (~20 minutes): fan coil cover removed, blower wheel and evaporator coil extracted. You’ll see the state of the coil before it’s cleaned — no hiding what was there.
  3. Chemical soak (~30–45 minutes): alkaline reagent applied, biofilm loosened, mould eradication treatment for the drainage tray.
  4. Rinse & reassemble (~20 minutes): coil pressure-rinsed with distilled water, blower reinstalled, mounting bracket re-checked.
  5. Test & vacuum (~15 minutes): system powered up, cold-discharge temperature measured, vacuum leak test performed. Before/after photos shared via WhatsApp.

Total on-site time: 90 minutes to 2 hours per unit, or around 3 hours for a full indoor + outdoor overhaul.

Signs You Need A Chemical Wash (Not Just Servicing)

  • Musty or “wet gym clothes” smell from the unit even after a fresh servicing
  • Water dripping from the fan coil cover despite a recent drainage clean
  • Cooling capacity has noticeably dropped (the bedroom that used to take 10 minutes now takes 30)
  • Visible black residue on the fan coil fins or blower wheel
  • Electricity bill has climbed 20–30% with no change in usage

If two or more of these apply, a chemical wash will almost certainly solve it. Routine servicing won’t.

What We Bring — And What Stays Clean

Our van carries: industry-grade alkaline reagent (non-corrosive, HDB-safe), pressure-rinse equipment, nitrogen tank for leak testing, vacuum pumps, new drainage-tray insulation, manufacturer-spec replacement filters, and a thermal imaging camera for the compressor check.

Your floors, walls and furniture stay untouched — drop cloth, vacuum, shoe covers every visit. That’s non-negotiable team policy.

How Our Service Works

Book Aircon Servicing In 5 Steps — No Phone Tag, No Hidden Fees

No phone-tag, no opaque quotes. Here is exactly what happens after you message us.

01

WhatsApp Us

Send a photo or video of the issue to +65 9182 5233. We confirm your slot within the hour, 9am to 6pm.

02

On-Site Diagnosis

Our technician arrives in a Coolbest van with a full kit. We inspect, test pressure, read error codes — then quote in writing.

03

Transparent Quote

Fixed quote, no hidden fees. If parts are needed, we show you the old ones and give you the replacement cost upfront.

04

Service & Test

Work is done cleanly — shoe covers, drop cloth, vacuum. We pressure-test, deodorize and re-check cooling before we leave.

05

90-Day Warranty

You get a signed invoice with the warranty terms. Same fault returns within 90 days? We come back free of charge.

Reviews

What Chemical Wash Customers Say

4.8 average across 200+ Google reviews. Real feedback from Jurong, Bishan, Boon Lay and beyond.

"Called Coolbest on Saturday morning because our bedroom AC was leaking onto the floor. Uncle came within three hours, found the drainage was clogged, cleaned it out and explained exactly what had happened. Paid S$70, no upsell. Will definitely book again."
Rachel T.
Jurong West
"Got all three units chemical washed before moving out of our condo in Bishan. They brought the Certificate of Service and our landlord released the full deposit without any fuss. Photos before and after made the difference."
Marcus L.
Bishan
"Installed a new Mitsubishi Starmex system for our HDB in Boon Lay. Mr Chong himself came to do the site survey, sized it right, and the team installed in one day. No leaks, no noise, running perfect six months in."
Farah A.
Boon Lay
FAQ

Chemical Wash — FAQs

If your question is not here, WhatsApp us — we answer within the hour during business hours.

How much does aircon servicing cost in Singapore?
General aircon servicing at Coolbest starts at S$50 for 1 unit and scales to S$115 for 6 units — a flat per-unit rate with no hidden charges. Chemical wash runs S$90–S$180 per unit depending on the system type. You get a written quote before any paid work begins.
Do you offer a warranty on aircon servicing and repairs?
Every service and repair at Coolbest is covered by a 90-day workmanship warranty. If the same fault returns within 90 days of our visit, we come back and fix it at no charge. The warranty is written on your invoice — no small print, no exclusions for 'normal wear'.
Do you service aircons in Bishan, Marine Parade and Central Singapore?
Yes — we cover the whole island. Our base in Jurong West means same-day response across the West Region, while Central areas like Bishan, Toa Payoh, Queenstown and Marine Parade are typically next-day. Travel is included in the per-unit price; no island-wide surcharge.
What's the difference between a chemical wash and a chemical overhaul?
A chemical wash dismantles the indoor fan coil and soaks it in alkaline solution — the right fix for mould, smell and weak airflow. A chemical overhaul goes further: we also remove the outdoor condenser, clean the compressor and reassemble with new insulation. Overhaul is usually recommended every 3–5 years for units older than 7 years.
How often should I service my aircon in Singapore?
Quarterly (every 3 months) for HDB flats and condos under normal use. Monthly for households with pets, allergies or heavy 24/7 running. Commercial spaces should service monthly to quarterly depending on foot traffic. Singapore's humidity grows mould faster than most climates — quarterly is the bare minimum.
Do you provide a Certificate of Service for end-of-tenancy handover?
Yes. Our end-of-tenancy package includes a signed Certificate of Service, before/after photos, and an invoice in the format most Singapore landlords accept. Book us 3–5 days before your handover date so there's buffer if anything needs a follow-up wash.
Next Step

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Ready To Book Your Chemical Wash?

WhatsApp +65 9182 5233 for same-day bookings across the West Region. 90-day warranty included, always.