Why Every Gas Top-Up Starts With a Leak Check
Aircon gas doesn’t get used up. Refrigerant moves round a sealed loop between the indoor and outdoor units.
If your unit is low on gas, there’s a leak somewhere. That’s why every aircon gas top-up we do starts with a leak check and a pressure test.
Our technician connects a manifold gauge to the service valve on the outdoor unit. They read the pressure on the suction line. If it’s low, they check the usual suspects: the flare joints where pipes meet the units, the copper piping itself, and any spot where the pipe insulation is damaged.
Helpling, a Singapore home services platform, notes that leaks in copper pipes usually come from poor connections, flaring issues or loosely tightened joints. A bubble leak test with soapy water shows even small leaks as tiny bubbles.
Then you decide. We tell you where the leak is, quote the fix, and top up once it’s sealed. You won’t pay for gas that escapes again in a few months.
Gas top-up starts from S$80, with a fixed quote and our 90-day workmanship warranty. For context, a 2026 guide from Homejourney puts typical Singapore top-ups at S$80 to S$150 per unit for R410A and S$100 to S$200 for R32. Your final quote depends on the gas type and where the leak is.
Signs Your Aircon Is Low on Gas
- Cooling drops slowly over weeks or months, not overnight
- A hissing sound near the indoor or outdoor unit
- Ice on the copper pipe at the outdoor unit, or on the indoor coil
- The compressor never cuts off, even when the room feels cool enough
- Oily marks at pipe joints, where refrigerant oil escapes with the gas
Low cooling isn’t always low gas. A dirty coil causes many of the same signs.
If a pressure test shows normal readings, a chemical wash or a not-cold diagnosis is the better next step. We’ll tell you that straight away instead of selling you gas.
Refrigerant Types We Top Up
| Refrigerant | Found in | Notes |
|---|---|---|
| R32 | Most newer units | Common in current inverter models, with a much lower global warming potential than R410A |
| R410A | Many units from the last 15 years | Widely used in inverter and multi-split systems, and still fine to run if your unit works well |
| R22 | Older units | Still found in many older Serangoon flats, and Singapore plans to ban R22 imports by 2030, according to a 2020 PassionAir overview |
Our technician checks the label on your outdoor unit before topping up. We never mix refrigerants.
If you have an older R22 unit, ask us about the cost of repair against replacement while we’re there. Gas for phased-out refrigerants can get harder to source over time.
Common Problems We Solve
Cooling fades a little every month
This is the classic slow leak. The gas escapes bit by bit until the room no longer gets cold.
Finding and sealing the leak stops the slide. A top-up alone only buys you a few months.
Ice on the outdoor pipe
Low pressure makes the pipe so cold that moisture freezes on it. Ice on the pipes is one of the standard signs of low refrigerant, alongside weaker cooling and hissing.
Once we top up the system to the right level, the frost stops forming. Switch the unit off and let the ice melt before we arrive, as running it while frozen strains the compressor.
One room in a multi-split is weaker
On System 2, 3 or 4 setups, low gas can show up as one room cooling less than the others. Many 3 and 4 bedroom HDB flats in Serangoon Central and Serangoon North run this kind of setup.
We test the shared outdoor unit before blaming a single room. That saves you from paying for repairs on an indoor unit that’s actually fine.
After the Top-Up
Keep an eye on cooling for the next few weeks. If it fades again, the leak has returned, and our 90-day warranty covers the same fault.
Regular general servicing every 3 to 4 months also helps. Our technician can spot early signs like oily joints before the gas runs low. Some Singapore providers suggest servicing as often as every 3 months in our humid climate, so this schedule is a sensible middle ground.
Need an aircon gas top-up in Serangoon? Book a leak check with us today, and we’ll give you a fixed quote before any work starts.