What type of refrigeration oil should I use for my screw compressor?

Screw compressors typically require POE (Polyol Ester) oils for HFC refrigerants like R134a and R407C, or mineral oils for HCFC systems like R22. The viscosity grade (usually ISO VG 32-68) depends on the compressor manufacturer's specifications. Brands like Bitzer recommend BSE series POE oils, while FUSHENG systems often use mineral oil formulations.

What is the difference between POE and mineral refrigeration oil?

POE (Polyol Ester) oils are synthetic lubricants designed for HFC refrigerants (R134a, R404A, R407C, R410A) and are hygroscopic, requiring careful moisture control. Mineral oils (MO) are petroleum-based, used with CFC and HCFC refrigerants (R22, R502), and are less expensive but incompatible with modern HFC systems. POE oils offer better thermal stability and miscibility with newer refrigerants.

How do I select the right refrigeration oil for a centrifugal chiller?

For centrifugal chillers, select oil based on the OEM specification (e.g., Trane OIL00037, York PureOil S), the refrigerant type (R123 low-pressure or R134a medium-pressure), and the required viscosity grade. Most modern centrifugal chillers use POE oils with ISO VG 32-68. Always verify compatibility with the chiller manufacturer's technical bulletin and ensure the oil meets the required pour point for your operating conditions.

Hitachi Refrigeration Oil: 3-Pronged Protection for Your Unit

By Qishanr Lubricants September 29th, 2025 73 views

1. Simplify Refrigerant Compatibility

Modern refrigeration systems rely on mixed refrigerants:

R22 (for older units)
R410A (for new eco-friendly units)
R134a (for refrigerated trucks)

Traditional oils require multiple stock types, increasing the risk of misselection and system failures.

✅ Hitachi’s Solution:Take its flagship model UX-300 (shown in the image above) as an example — made with high-performance POE (polyol ester) synthetic base oil, it works seamlessly with:

HFCs (R134a, R410A, etc.)
HCFCs (R22)
Even some CFC systems

One oil fits all scenarios, slashing procurement and maintenance costs.

2. Withstand Extreme Temperatures

Extreme weather poses critical threats to units:

Frigid winters (-30°C): Inferior oil solidifies, clogging pipelines.
Scorching summers: Overloaded compressors push oil temperatures to dangerous levels.

✅ Hitachi’s Advantage:UX-300 is engineered to handle extremes:

Pour point: -42°C → Stays fluid in freezing conditions.
Flash point: 270°C → Eliminates fire/explosion risks (far above normal discharge temperatures).

Guarantees 24/7 stable operation, no matter the weather.