Bitzer Reciprocating Compressor
Bitzer semi-hermetic reciprocating compressors are one of the mainstream compressor solutions for pharmaceutical cold rooms (2°C~8°C).
Brand Positioning
Item Information
Founded 1934, Sindelfingen, Germany
Status One of the world's leading refrigeration compressor manufacturers, the only one mastering piston/screw/scroll technologies
China Entered in 1994, production base in Beijing E-Town, over 1.5 million units in domestic use
2024 Performance 4,500 employees globally, sales of €1.12 billion
Reciprocating Compressor Product Line (Related to Pharmaceutical Cold Rooms)
Series Positioning Power Range Features
ECOLINE (New Generation) Mainstream for medium/high-temperature commercial use 2~15HP COP improved by 12% vs. previous generation, built-in oil separator, compact design
4J / 4H / 4G / 4F Classic semi-hermetic 0.37~74kW Durable valve plate, wear-resistant bearings, internal oil return system
6G / 6F / 6E / 6D High-capacity continuous operation Medium to large 6-cylinder layout, vibration ≤0.05mm, supports 25%~100% stepless capacity regulation
Two-stage Reciprocating (V/W Type) Low-temperature applications -40°C~-50°C Choose this when single-stage is insufficient; generally not needed for pharmaceutical cold rooms
4DC / 4CC (Octagonal) Compact installation Small capacity C1~C4 octagonal design, suitable for compact machine rooms
For pharmaceutical cold rooms (2°C~8°C), the mainstream choice is the ECOLINE or 4J/4H series, which is fully sufficient; two-stage is not required.
Core Parameters Matching Pharmaceutical Cold Rooms
Parameter Data
Refrigerants R134a, R404A, R507A, R407C, R744 (CO₂)
Single-stage Evaporating Temperature Down to -40°C (pharmaceutical rooms only need around 0°C, ample margin)
Compression Ratio Tolerance 12:1, no performance degradation at high or low temperatures
Capacity Regulation Unloader cylinder head: 4-cylinder can unload to 50%, 6-cylinder can unload to 66%/33%; ECOLINE supports variable speed
Motor Cooling Suction gas cools the motor, automatic protection when return gas is insufficient (INT69VS module)
Noise ≤58dB (six-cylinder)
Selection Recommendations (for Pharmaceutical Cold Rooms)
Cold Room Size Recommended Model Reason
Small (<50㎡) ECOLINE 4-cylinder + unloader cylinder head High efficiency, partial load unloads to 50%, energy saving
Medium (50~300㎡) 6-cylinder series (6G/6F) Stable continuous operation, low vibration, GSP validation friendly
Vaccine Storage (requires 2 independent rooms) Each room equipped with 4~6-cylinder semi-hermetic Meets GSP requirement of "at least 2 independent cold rooms for vaccine operations"
Refrigerant selection: For new installations, R449A / R452B (low-GWP alternatives to R404A) are recommended; the entire Bitzer range is compatible.
Operation & Maintenance Notes
Common Fault Cause Remedy
Low oil pressure Dirty refrigerant oil / oil blockage Clean oil filter, replace oil
Motor INT69VS protection Insufficient return gas, motor overheating Increase refrigerant circulation, reduce superheat
Liquid slugging (abnormal noise at startup) Incomplete evaporation, liquid returning to compressor Close liquid line valve slightly, increase expansion valve superheat
Valve plate breakage Oil slugging or liquid slugging Replace valve plate, drain excess refrigerant oil
Start/stop frequency limits (must be observed, otherwise motor burnout):
≤7HP: 10 starts/hour, each run >2 minutes
8~20HP: 10 starts/hour, each run >3 minutes
22~40HP: 8 starts/hour, each run >5 minutes
>40HP: 5 starts/hour, each run >8 minutes
