R-407C vs R-22 Refrigerant
A comprehensive technical retrofit guide for converting legacy R-22 air conditioning and commercial heat pump systems to non-ozone-depleting R-407C. Master lubricant flush, expansion valve adjustments, and operating pressures.
R-407C · 25 lb Cylinder
A1 non-flammable ternary blend (R-32 / R-125 / R-134a) exhibiting operating pressures and cooling capacities closely matching R-22. Requires POE lubricant conversion.
R-22 (Freon 22)
Class II ozone-depleting HCFC refrigerant prohibited from virgin manufacture and import under the Clean Air Act. Servicing relies on existing recovered/reclaimed stocks.
Side-by-Side Technical Comparison
| Technical Parameter | R-407C (Suva 407C) | R-22 (Freon 22) |
|---|---|---|
| ASHRAE Safety Group | A1 (Non-Flammable) | A1 (Non-Flammable) |
| Chemical Classification | HFC Blend (23% R-32 / 25% R-125 / 52% R-134a) | Pure HCFC (Chlorodifluoromethane) |
| Ozone Depletion Potential (ODP) | 0.00 (Zero Ozone Depletion) | 0.055 (Ozone Depleting) |
| Global Warming Potential (GWP) | 1,774 | 1,810 |
| Standard Net Cylinder Weight | 25 lb (Factory-Sealed Cylinder) | Legacy 30 lb Cylinder |
| Operating Pressures | Close match (~95% to 105% of R-22) | Baseline standard (~225-260 PSI discharge) |
| Temperature Glide | ~9°F to 11°F (Moderate glide, liquid charging mandatory) | 0°F (Single component, vapor or liquid charging) |
| Required Lubricant | POE (Polyolester) Oil (Residual MO must be < 5%) | Mineral Oil (MO) or Alkylbenzene (AB) |
| Cooling Capacity & Efficiency | Matches R-22 within ±5% across AC applications | Baseline standard |
Is R-407C a direct drop-in replacement for R-22?
No. R-407C cannot be directly topped off into an R-22 system without complete lubricant conversion. Because R-407C is insoluble in traditional mineral oil, failure to flush and replace the oil with POE will prevent oil return, resulting in compressor seizure.
A proper retrofit procedure requires: 1) Full recovery of all existing R-22, 2) Flushing lubricant until residual mineral oil is under 5%, 3) Replacing liquid line filter-driers and elastomeric seals, 4) Charging R-407C strictly in the liquid phase to preserve blend composition, and 5) Relabeling the equipment with R-407C and POE identifiers per EPA guidelines.