January 20, 2026
•6 min read
•By Technical Specialist Wong K.
A neighbourhood "gas top-up" is still sold as a comfort product in Malaysia. The pitch is simple: if the room is warm, add refrigerant. On R32 inverter splits that shortcut is how scroll compressors ingest liquid, amp draw climbs, and the thermal protector starts cycling the outdoor unit off just as guests arrive.
R32 and R410A are different fluids with different saturation pressures. A gauge reading that looks "healthy" for one is a severe overcharge for the other. Weigh the charge; do not hunt for a folklore PSI number.
01
The Extra-Gas Myth
Cooling capacity comes from mass flow through a clean coil and a correctly charged circuit. Extra liquid in the accumulator or condenser raises head pressure, raises compressor work, and can slug the scrolls with incompressible liquid on the next start.
Warm air is often not a gas shortage
Biofilm on the indoor coil, a failing outdoor fan, or a tripped inverter current limit all mimic "low gas." Adding refrigerant into those faults overcharges a system that was never empty.
Check Delta-T first Confirm refrigerant type on the rating plate Never mix R32 and R410A
02
R32 vs R410A Operating Windows
Field suction on a healthy R32 wall split in KL conditions often sits in a tighter band than older R410A folklore numbers. Treat published PSI here as orientation, not a DIY setpoint. Ambient, indoor wet bulb, and inverter speed all move the needle.
Orientation only
See nameplateR32 suction vs overcharged amp penalty
R32 typical running windowOvercharge amp climb
Charted against indoor wet bulb+amp draw, slugging risk
If suction is already high and the compressor is hot and loud, stop. Recover and weigh. Do not add more because the room is still 27°C.
03
How We Charge Correctly
Correct charge is a measured process after leak isolation. Chemical wash or drain work may be required first if airflow is the actual bottleneck.
01
Identify the fluid
Read the outdoor rating plate. R32 systems use different cylinders, hoses, and recovery rules than R410A.
Phase 1 Identity
02
Find the leak if empty
A system that is truly low has a hole. We trace before refill so the same kilogram does not leave again in a week.
Phase 2 Integrity
03
Weigh, then verify
Charge by mass where the manufacturer requires it, then confirm Delta-T and running amps—not a single suction number.
Phase 3 Verify
04
Warm Air vs Overcharge vs Leak
Match symptoms before anyone connects a cylinder.
| Symptom | Often means | Do not |
|---|---|---|
| Warm air, iced suction, hissing | Restriction or genuine undercharge / leak | Keep adding gas |
| Warm air, dirty filters, weak throw | Airflow / coil biofilm | Treat as low gas |
| Outdoor very hot, high amps, short cycle | Overcharge or condenser blockage | Force another restart |
| Recent "top up," now tripping MCB | Possible slugging / PCB stress | Add more refrigerant |
05
When the Motor Is Already Hurt
If the compressor knocks, the overload cycles every few minutes, or the inverter board has already faulted, stop. Part replacement is quoted after diagnosis—never from a gas-top-up invoice.
Amp draw tells the story
A compressor pulling well above nameplate on a "full" charge is not undergassed. Recover and inspect.
Boards fail after abuse
Repeated hard starts from overcharge take out inverter modules. That is a part-replacement path, not another cylinder.
Book troubleshooting first
We confirm fluid type, leak status, and coil airflow before any recharge is sold.