Julabo FPW91-SL Ultra-Low Temperature Circulating Chiller
| Brand | Julabo |
|---|---|
| Origin | Germany |
| Model | FPW91-SL |
| Instrument Type | Split-System Circulating Chiller |
| Cooling Method | Water-Cooled |
| Temperature Range | –91 °C to +100 °C |
| Temperature Stability | ±0.25 °C at –91 °C, ±0.05 °C at 20 °C |
| Cooling Capacity | 200 W at 20 °C |
| Circulation Pump Pressure | 0.4–0.7 bar (discharge), 0.2–0.4 bar (suction) |
| Flow Rate | 22–26 L/min |
| Reservoir Volume | 8–27 L |
| Operation Mode | Continuous |
| Compliance | CE, RoHS, ISO 9001-certified manufacturing |
Overview
The Julabo FPW91-SL is an ultra-low temperature split-system circulating chiller engineered for demanding laboratory and industrial applications requiring precise thermal control down to –91 °C. Utilizing a cascade refrigeration system with environmentally optimized HFC-based refrigerants, the FPW91-SL achieves rapid cooldown while maintaining high thermal stability across its full operating range (–91 °C to +100 °C). Its water-cooled condenser design enables stable performance in ambient environments where air-cooled units would suffer from capacity derating or compressor cycling. The unit integrates dual-pump architecture — a high-pressure discharge pump and a dedicated suction pump — enabling reliable circulation of high-viscosity heat transfer fluids (e.g., silicone oils, ethylene glycol/water mixtures) through external jackets, reactors, calorimeters, or calibration baths. Designed for integration into GLP-compliant workflows, the FPW91-SL supports traceable temperature logging and meets essential requirements for ISO/IEC 17025-accredited calibration labs.
Key Features
- Ultra-low temperature capability: Stable operation at –91 °C, verified per DIN EN 61000-3-2 for electromagnetic compatibility and IEC 61000-4-3 for radiated immunity
- Dual-pump system with electronically adjustable pressure: Discharge pressure 0.4–0.7 bar; suction pressure 0.2–0.4 bar; automatic viscosity compensation ensures consistent flow under varying fluid conditions
- Split-system configuration: Condensing unit mounted remotely (e.g., utility room), minimizing lab-space footprint and acoustic impact (<58 dB(A) at 1 m)
- Stainless steel reservoir (8–27 L adjustable volume) with level sensor, leak detection, and integrated filtration
- Intelligent PID control with adaptive tuning: Maintains ±0.25 °C stability at –91 °C and ±0.05 °C at 20 °C per internal PT1000 sensor calibration
- Modular expansion support: Optional HST auxiliary heater (6 kW, extends upper limit to +150 °C) and HSP high-flow booster pump (30 L/min, 3 bar) for large-volume or high-backpressure applications
Sample Compatibility & Compliance
The FPW91-SL accommodates a broad spectrum of heat transfer media including aqueous glycol solutions (up to 60 % v/v), synthetic polyalphaolefin (PAO) oils, and silicone-based fluids (e.g., DC200 series). Its sealed refrigerant circuit and corrosion-resistant wetted materials (316 stainless steel, EPDM seals, borosilicate glass sight gauge) ensure long-term compatibility with aggressive solvents used in low-temperature reaction chemistry. The system complies with EU Machinery Directive 2006/42/EC, Pressure Equipment Directive 2014/68/EU (for reservoir and piping), and carries CE marking. It supports audit-ready documentation per FDA 21 CFR Part 11 when paired with Julabo’s optional LabSoft software (with electronic signature, audit trail, and user access levels).
Software & Data Management
Julabo LabSoft v5.2 (optional) provides full remote monitoring and control via Ethernet or USB. The software records time-stamped temperature, pressure, flow, and power consumption data at user-defined intervals (1 s to 60 min), exports CSV/Excel-compatible logs, and generates IQ/OQ protocols for validation. All data entries include operator ID, timestamp, and reason-for-change fields — satisfying ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available). Firmware updates are digitally signed and validated prior to installation to ensure integrity.
Applications
- Low-temperature calibration of thermocouples, RTDs, and infrared sensors per ASTM E230/E230M and ISO/IEC 17025
- Thermal conditioning of cryogenic viscometers, DSC sample stages, and dilatometry cells
- Temperature control for jacketed glass reactors in pharmaceutical process development (e.g., Grignard, lithiation, hydrogenation)
- Ice point determination and freezing-point depression studies in fuel and lubricant testing (ASTM D97, D2386)
- Stabilization of laser cavities, CCD detectors, and superconducting magnet cooling loops
- Support for accelerated stability testing chambers requiring sub-ambient setpoints
FAQ
What is the minimum achievable temperature with standard heat transfer fluid?
The FPW91-SL reaches –91 °C using Julabo’s recommended F120 synthetic oil (flash point >200 °C); aqueous glycol mixtures are limited to –40 °C due to freezing.
Can the unit operate continuously at –90 °C without degradation?
Yes — designed for 24/7 operation at rated load; compressor duty cycle is managed via intelligent oil return and subcooling control to prevent slugging or overheating.
Is remote alarm notification supported?
Via LabSoft with SMTP/email or SNMP trap configuration; dry-contact relay outputs (NO/NC) also available for building management system integration.
How is temperature uniformity ensured across large external systems?
By maintaining flow rates ≥22 L/min and pressure head ≥0.4 bar, the dual-pump architecture minimizes thermal lag and axial gradients in recirculating loops up to 50 m total length.
Does the FPW91-SL meet GMP requirements for pharmaceutical QC labs?
When validated with LabSoft and operated under documented SOPs, it fulfills Annex 11 and USP criteria for analytical instrument qualification (AIQ) and periodic requalification.
