BUCHI F-305 Recirculating Chiller
| Brand | BUCHI |
|---|---|
| Origin | Germany |
| Manufacturer | BUCHI AG |
| Type | Integrated Circulating Chiller |
| Cooling Method | Water-Cooled |
| Temperature Range | –10 °C to +25 °C |
| Refrigeration Capacity | 800 W |
| Temperature Stability | ±0.1 °C |
| Pump Pressure | 0.6 bar |
| Flow Rate | 2.5 L/min |
| Reservoir Volume | 3.0 L |
| Operating Mode | Continuous |
| Refrigerant | R134a |
| Power Supply | 230 V ±10%, 50/60 Hz |
| Max. Power Consumption | 850 W |
| Display Resolution | 0.1 °C |
| Control Accuracy | ±1.0 °C |
| Hose Connector | 8 mm |
| Dimensions (W×H×D) | 280 × 500 × 400 mm |
| Weight | 31 kg |
Overview
The BUCHI F-305 Recirculating Chiller is an integrated, water-cooled temperature control system engineered for precision and reliability in demanding laboratory environments. Based on vapor-compression refrigeration using environmentally compliant R134a refrigerant, the F-305 delivers stable, continuous cooling across a wide operational range of –10 °C to +25 °C. Its microprocessor-based PID temperature controller ensures high reproducibility with real-time monitoring of both setpoint and actual bath temperature at 0.1 °C resolution. Designed specifically for seamless integration with BUCHI’s Rotavapor® R-300 rotary evaporator systems—and compatible with a broad range of external heat-exchange devices—the F-305 provides constant flow (2.5 L/min), consistent pressure (0.6 bar), and minimal thermal drift (±0.1 °C stability), making it suitable for applications requiring sustained thermal management under variable load conditions.
Key Features
- Integrated architecture with compact footprint (280 × 500 × 400 mm), optimized for space-constrained benchtop installations
- Dual-circuit operation supporting both internal reservoir circulation and external closed-loop cooling loops
- Low-noise centrifugal pump with corrosion-resistant wetted parts and self-priming capability
- ECO mode functionality—automatically reduces compressor activity during idle periods when paired with BUCHI Interface I-300/I-300 Pro
- Temperature lock function prevents inadvertent parameter changes during routine operation
- Drain valve positioned at reservoir base for complete fluid exchange and maintenance compliance
- Front-panel navigation interface with intuitive button layout and dual-line LED display
- R134a refrigerant compliant with EU F-Gas Regulation (EU No 517/2014) and global ozone depletion potential (ODP = 0) standards
Sample Compatibility & Compliance
The F-305 is designed for use with aqueous and water-glycol mixtures (up to 30% v/v) in closed-loop configurations. Its stainless steel and EPDM-sealed fluid path resists degradation from prolonged exposure to deionized water or mild corrosion inhibitors. The unit meets IEC 61010-1:2010 safety requirements for laboratory electrical equipment and carries CE marking per the European Machinery Directive 2006/42/EC. While not intrinsically rated for hazardous area use, its construction supports GLP-compliant documentation workflows when deployed in regulated QC/QA laboratories. All firmware operations—including temperature logging, ECO activation, and pump status—are timestamped and traceable, facilitating alignment with FDA 21 CFR Part 11 principles where electronic records are archived externally.
Software & Data Management
The F-305 operates autonomously without mandatory software dependency; however, optional integration with BUCHI’s Interface I-300 or I-300 Pro enables centralized parameter configuration, multi-device synchronization, and remote status monitoring via RS232 or USB. Temperature setpoints, actual bath readings, pump runtime, and ECO mode transitions are logged internally with time/date stamps. Exportable CSV files support post-acquisition analysis in third-party platforms (e.g., LabArchives, Empower, or custom LIMS). Audit trail generation is achievable through external data capture systems, satisfying traceability needs in ISO/IEC 17025-accredited testing facilities.
Applications
- Cooling condensers in rotary evaporation (especially Rotavapor® R-300 systems) to maintain optimal solvent recovery efficiency
- Thermal stabilization of HPLC column ovens, UV-Vis detectors, and mass spectrometer interfaces
- Heat dissipation for laser sources, CCD cameras, and other optoelectronic instrumentation requiring low-temperature operation
- Controlled cooling of reaction blocks in parallel synthesis stations and automated chemistry platforms
- Support of calorimetric measurements where baseline thermal drift must remain below ±0.1 °C over extended durations
FAQ
What is the maximum allowable ambient temperature for continuous operation?
The F-305 is rated for continuous duty at ambient temperatures up to 30 °C, provided adequate ventilation clearance (≥10 cm on all sides) is maintained.
Can the F-305 be used with ethylene glycol solutions?
Yes—water/glycol mixtures up to 30% v/v are compatible; viscosity increase must be accounted for in system pressure drop calculations.
Is the reservoir volume sufficient for integration with large-volume condensers?
With a 3.0 L reservoir and 2.5 L/min flow rate, the F-305 is optimized for standard benchtop evaporators and analytical instruments; for high-flow applications (>4 L/min), external reservoir expansion kits may be required.
Does the unit support external temperature feedback control?
No—the F-305 regulates based on internal bath sensor input only; external probe integration is not supported in firmware.
How often should the refrigerant charge be verified?
Under normal operating conditions and absence of physical damage, R134a integrity remains stable for ≥8 years; verification is recommended during annual preventive maintenance per BUCHI Service Bulletin SB-F305-2023.

