Aircon Gas Top-Up in Singapore
Low refrigerant reduces cooling, but adding gas to a leaking system is a temporary fix. We check system pressure before topping up to confirm whether the gas loss is normal or a sign of an underlying leak.
What Is Gas Top-Up
A refrigerant top-up restores the charge in the system's refrigerant circuit to the manufacturer's specified level. Gas does not get consumed during normal operation — if the level is low, the system has either had a slow leak over many years, or a faster one that needs addressing. The pressure check before any top-up tells us which situation we are dealing with. R22, R410A, and R32 are not interchangeable: each operates at different pressures with different oil requirements. Using the wrong type damages the compressor.
Common Symptoms
Low refrigerant produces consistent symptoms. These do not always mean low gas — but they are the starting point for investigation.
Air blows but not cold
The most common sign. The unit is running but has insufficient refrigerant to transfer heat effectively — airflow is normal but temperature is not.
Ice on indoor coil or piping
Low refrigerant causes the evaporator coil to overcool. Moisture in the air freezes on the coil surface or the suction line before it can be managed.
Compressor runs non-stop without reaching temperature
The system keeps trying to hit the set temperature but cannot — there is not enough gas in the circuit to complete the heat exchange.
Hissing from the indoor unit
Audible hissing near the indoor unit or piping connections can indicate refrigerant escaping at a joint, valve, or flare fitting.
Refrigerant Types
Every system is designed for a specific refrigerant. We confirm the type from the unit nameplate before any top-up.
- 01
R22 (legacy systems)
Found in units installed before approximately 2015. Being phased out globally under the Montreal Protocol. Still serviceable in Singapore, but supply is tightening and prices are rising. Not interchangeable with R410A or R32.
- 02
R410A (current standard)
The standard refrigerant for residential split systems in Singapore since 2015. Operates at significantly higher pressure than R22 — equipment, hoses, and fittings must be rated for R410A. The two types cannot be mixed.
- 03
R32 (newer systems)
Used in recent inverter models from Daikin, Panasonic, Mitsubishi, and others. Better energy efficiency and a lower global warming potential than R410A. Requires specific handling due to mild flammability.
How We Handle It
The top-up itself is straightforward. The steps before it are where the work happens.
- 01
Pressure check
Manifold gauges measure the system's operating pressure. This confirms whether refrigerant is low, and by how much — and whether the pressure is holding or dropping.
- 02
Leak assessment
If pressure is low and not holding, we identify whether there is an active leak before recommending a top-up. Adding gas to a leaking system is a short-term fix — it will escape again.
- 03
Top-up and verify
Once pressure holds, we add the correct refrigerant type in the measured quantity. The system is run to confirm stable operating pressure and restored cooling performance.
Benefits of Gas Top-Up
What changes when the refrigerant level is correctly restored.
Cooling restored
The system can complete the refrigerant cycle at the designed efficiency, reaching set temperature again.
Leak assessed before adding gas
We do not top up blind. If there is a leak, you know about it before deciding how to proceed.
Right gas, right quantity
Refrigerant is matched to the system type and measured before and after. No guesswork, no overfill.
System verified after top-up
Run under load to confirm stable pressure and consistent cooling performance before we leave.
When to Book Gas Top-Up
These situations are where a top-up is the appropriate starting point.
Air blows but is not cold
The clearest signal that refrigerant level may be low.
Ice forming on the indoor coil or piping
Low charge causes the evaporator to overcool and freeze surface condensation.
Compressor running non-stop without reaching the set temperature
Insufficient gas means the heat exchange cycle cannot complete.
After a repair involving refrigerant lines
Piping joints, valve replacements, or brazed connections may need recharging after work.
After a pressure test confirms no active leak
Top-up is appropriate once the system is confirmed to hold pressure.
When Gas Top-Up Is Not the Right Call
Adding refrigerant does not fix every cooling problem — and in some cases it should not be done at all until something else is resolved first.
Pressure dropped significantly within months of the last top-up
An active leak needs to be found and repaired before topping up again.
System is completely empty
Something has failed. Leak repair is mandatory before recharging; gas added to an empty system will escape at the same rate.
Unit is not cooling but gas level is normal
Refrigerant is not the issue. The fault is elsewhere — airflow, compressor, expansion valve, or controls.
Unit is not starting
An electrical or compressor fault, not a refrigerant problem. Topping up will not help and should not be attempted.
Gas Top-Up FAQ
Gas Top-Up Rates
Pricing by refrigerant type. Range depends on how much gas the system needs — we measure before and after. We cover all areas of Singapore, Monday to Saturday. See the full price list for all services.
| Service | 3+3+ units | 22 units | 11 unit |
|---|---|---|---|
| Gas top-up | |||
| R410A | $80–$150 | ||
| R32 | $120–$200 | ||
| R22 | $60–$100 | ||
Related Reading
Guides, troubleshooting, and real cases to help you make informed decisions.