How do I know if my aircon has a gas leak?

Signs of an aircon gas leak

One of the refrigerant leak signs you can notice yourself is a smell. Daikin Singapore says a smell like exhaust fumes may mean a leak in the refrigerant line, and that a refrigerant leak affects performance and can release chemicals into your home. To find out whether a smell comes from the aircon at all, Daikin suggests switching the aircon off: if the smell goes away, it was the aircon.

The other common sign is weak cooling, but that has simpler causes too. Before you blame refrigerant, run through the checks on Daikin's troubleshooting page for an aircon that does not cool well: the temperature and mode set on the remote, the air quantity and direction, whether the filters are clean, whether anything blocks the units, and whether windows and doors are closed. This is Daikin's global page, so follow your own model's manual too. Our aircon not cold guide looks at other reasons a room stays warm.

Other signs, such as ice on the unit or weak airflow, are reasons to ask a technician to take a look, not proof of a leak. A hiss on its own is not proof of an aircon hissing gas either: Daikin's troubleshooting page notes that a hissing or crackling sound on models with Streamer discharge is not a malfunction.

Is refrigerant dangerous indoors?

Daikin Singapore says to call a professional right away if you suspect a refrigerant leak, and to open the windows to ventilate while you wait.

On its R-32 refrigerant page, Daikin classes R-32 as Class 2L, or lower flammability, with a burning velocity under 10 centimetres per second. Lower flammability still means it can burn, so a leak is not harmless: keep flames away and ventilate.

The National Environment Agency (NEA) says hydrofluorocarbons, commonly used as refrigerants in aircons and refrigerators, are potent greenhouse gases. Since 2022, split-type household aircons supplied in Singapore, both inverter and non-inverter models up to 17.6 kW, must use a refrigerant with a global warming potential (GWP) of no more than 750. Units supplied before then are not affected.

Leak test, repair and top-up order

Topping up without fixing the leak only delays the problem, so work in this order.

1. Switch off and ventilate. Turn the aircon off and open the windows while you wait for help.
2. Book a technician to find the leak. Ask for a leak check, not only a top-up, and describe the signs you noticed.
3. Repair the leak. Ask the technician to show you where the leak is and explain the repair before work starts.
4. Top up or recharge the refrigerant. Only after the repair should the system be topped up or recharged.
5. Check the cooling. Run the aircon afterwards and confirm the room cools with clean filters and correct settings.

Ask who will handle the refrigerant. NEA says that, to comply with the Singapore Civil Defence Force (SCDF) requirements on handling R-32 aircon systems, manufacturers must ensure service personnel have completed training courses run by the Institute of Technical Education (ITE). ITE runs a Certificate of Competency in Residential Air-Conditioning System (Refrigerant) course for household aircon technicians, and NEA publishes a list of technicians who have completed it. Ask whether your technician has.

When you are ready to book, you can compare companies that offer an aircon gas top-up in the directory.

What a gas top-up costs

In the directory, 26 companies publish a gas top-up line. The units are mixed: per unit, per job, per kg, per psig, and some lines are printed without a unit. Of these, 17 price it per unit: their lowest per unit rates run from S$30 to S$90 per unit, with S$60 in the middle (the middle company's own published rate, not an average).

Most per unit lines are ranges, for example S$40 to S$80 per unit, because the charge depends on how much gas is needed. Per kg and per psig lines are shown as printed, so check each line's unit before you compare.

FROM THE HOMEZYPRO DIRECTORY

Published gas top-up rates

For the most common unit (per unit), the lowest published rates from 17 companies run from S$30 to S$90. Each figure is one company's own advertised rate with its conditions, not a market average or a quote.

See 26 published gas top-up rates and sources

Lowest matching advertised rate per company, in SGD as published. "From" marks a starting price and ranges are shown in full. Check the source for minimums, GST and inclusions.

Company	Service as listed	Rate	Source
Coolman Aircon Servicing Pte Ltd	R22 Gas	S$30 to S$90 per unit	coolmanaircon.com.sg
Homeone Aircon	Refrigerant gas R32	S$35 per kg	homeone.com.sg
5 Star Aircon Pte Ltd	R22 Gas	S$40 to S$80 per unit	5staraircon.sg
Airconman Sg Pte Ltd	Gas topping, R22	S$40 to S$120	airconman.sg
Airmaxx Aircon Pte Ltd	Gas top-up, R22	S$40 to S$120	airmaxxaircon.com
City Cooling Pte Ltd	Gas top-up, R22	S$40 to S$80 per unit	citycoolingengr.com.sg
Sky Shine Air Conditioning Pte Ltd	Gas Topping Pricing	S$40 to S$80 per unit	skyshineaircon.sg
SmartCool Aircon Servicing Singapore	Gas top-up, R22	S$40 to S$120 per unit	smartcool.sg
Bioaire Air Conditioning Solutions	R22 Gas	S$50 to S$150 per unit	bioaireaircon.com.sg
Citicool Engineering Pte Ltd	Aircon gas (refrigerant) top up, R22	S$50	citicoolaircon.com
Cooling Guard Pte Ltd	R22 GAS	S$50 to S$100 per unit	airconservicessg.com
L-Cool Engineering Pte Ltd	R22 Gas	S$50 to S$100 per unit	lcoolairconservice.com
Konnect Aircon Servicing	Gas top-up	From S$60 per unit	konnect.com.sg
Same Day Aircon Servicing Repair	Gas top-up	From S$60 per unit	urgentairconservicing.sg
Snowflake Services LLP	Gas top-up, R22	S$60 to S$100 per unit	snowflakeaircon.sg
Thetop Aircon Service	Gas top-up, R22	S$60 to S$140 per unit	thetop.com.sg
Purer Fresher Air	R22 GAS	S$70 to S$130 per unit	airconservice.com.sg
AC Aircon Services	Replenish of Aircon Refrigerant Gas	S$80 to S$250 per unit	acairconservices.com
Airvice Chapter	Refrigerant gas top-up, R22	S$80 to S$100 per unit	airvicechapter.com
Easy Cool Engineering Pte Ltd	Gas top-up, R410A	S$80 to S$150	easycool.sg
EC Aircon Services Pte Ltd	Gas top-up, R22/R410	S$80 to S$150 per unit	ecaircon.com
Lion City Air Conditioner Services	Gas top-up	S$87.20 to S$218 per job	lioncityaircon.sg
Cool Aircon	Gas top-up, R22 (under 40 PSI)	S$90 to S$130 per unit	coolaircon.sg
THL HQ Aircon	Gas top-up, minor (below 50 PSI)	S$90 per job	thl-aircon.com.sg
L-Tech Aircon Services	R22 Gas	S$120 to S$150 per psig	ltechaircon.com.sg
Aircon Uncle	Aircon gas top-up	From S$128 per job	airconuncle.com.sg

See our aircon gas top-up cost guide for more on these rates.

When to stop and call a professional

Call a technician if any of these apply:

• You notice a smell like exhaust fumes from the unit.
• Cooling stays weak after you clean the filters and check the settings.
• You were told the unit needs gas again soon after a top-up.
• There is any smell near a flame or cooker: switch the aircon off and ventilate the room.

For a leak that needs fixing, look for companies that list aircon repair, or browse all aircon companies with their published prices and the areas they say they cover.

Questions