Refrigerant Leak Detection — Soap Bubble / Electronic / Tracer Gas / UV Dye

Pros/cons by method + when to use each

Check: **① Soap bubble** (microfoam): clear visible leak. Use on flares, service ports, exposed sections. Limit = insulated areas/embedded piping. Microfoam = 5×+ more stable bubbles than regular soap. **② Electronic detector**: ppm-level refrigerant sensing. R-32 = A2L-compatible mandatory. Use on insulated areas and outdoor body. Limit = accuracy drops in wind. **③ Tracer gas** (hydrogen/helium): highly precise, can trace embedded piping. Limit = expensive gear (KRW 2M+). Used in industrial/large VRF. **④ UV dye**: add dye, trace with UV lamp. Limit = residue persists for future inspections (confusion on reuse).

What to do: **Standard field procedure** (small–medium): ① **Visual + soap bubble first** (whole system). Watch 10–15 min — small leaks bubble slowly. ② **Electronic detector second** (inside outdoor unit, on insulation exterior). ≥50 ppm = leak confirmed. ③ If both miss = **pressurize and watch 1-hour pressure decay** (nitrogen leak test applied). ④ Still not found = **tracer gas or UV dye**. **After locating**: recover → repair (braze/re-flare) → vacuum → weighed recharge.