Great Wall DL-400 Integrated Circulating Chiller for Small-Scale Rotary Evaporation

Overview

The Great Wall DL-400 Integrated Circulating Chiller is an engineered thermal management solution specifically designed to support small-scale rotary evaporation systems in analytical, synthetic, and quality control laboratories. It operates on a vapor-compression refrigeration cycle, utilizing a hermetically sealed, high-reliability compressor to maintain precise low-temperature coolant delivery under continuous load. Unlike modular or external chillers requiring separate pump integration, the DL-400 integrates refrigeration, circulation, and reservoir functions into a single compact chassis—enabling stable condensation performance for rotary evaporators with evaporation flasks up to 2 L capacity. Its −15 °C to 25 °C operational range supports solvent recovery across a broad polarity spectrum, including acetone, ethyl acetate, dichloromethane, and ethanol, while its ±2 °C temperature stability ensures reproducible distillation endpoints critical for method validation and inter-laboratory comparability.

Key Features

• Integrated architecture eliminates external pump coupling and tubing complexity—reducing leak points and priming failures.
• 360° rotatable fluid couplings facilitate ergonomic connection to rotary evaporator condensers, vacuum manifolds, and jacketed reactors without torsional stress on hoses.
• All wetted components—including reservoir, pump head, and internal piping—are constructed from ANSI-grade 304 stainless steel and chemically resistant polymer alloys (e.g., PTFE-lined seals, EPDM diaphragms), ensuring compatibility with organic solvents and mild aqueous acids/bases.
• Industrial-grade hermetic compressor delivers consistent 400 W cooling output at 20 °C ambient, with thermal overload protection and automatic restart after power interruption.
• Low-profile footprint (W × D × H ≈ 280 × 350 × 420 mm) enables benchtop placement adjacent to rotary evaporators or floor-standing installation where space permits.
• Continuous-duty operation certified for unattended 24/7 use in GLP-compliant environments when paired with compatible evaporation systems.

Sample Compatibility & Compliance

The DL-400 is validated for use with standard rotary evaporation configurations employing water-cooled or dry-ice-assisted condensers. Its 3 L reservoir volume and 17 L/min flow rate provide sufficient thermal mass and convective heat transfer to sustain condenser surface temperatures ≤5 °C during sustained evaporation of volatile solvents at ≤40 °C bath temperature. The unit complies with IEC 61000-6-3 (EMC emissions) and IEC 61000-6-2 (immunity), and meets CE marking requirements for laboratory equipment. While not intrinsically rated for Class I Division 1 hazardous locations, its non-sparking pump motor and grounded metal enclosure align with general laboratory safety best practices per ANSI Z9.5 and ISO 15195. No modifications are required to support IQ/OQ protocols under FDA 21 CFR Part 11–governed workflows when integrated with validated evaporation platforms.

Software & Data Management

The DL-400 operates via a dedicated analog/digital hybrid control panel featuring LED temperature display, manual setpoint adjustment (0.1 °C resolution), and real-time status indicators for compressor activity, flow continuity, and reservoir level. It does not include embedded microprocessor-based data logging, remote connectivity (e.g., RS-485, Ethernet), or PC interface firmware. However, its stable analog output signal (0–5 V DC proportional to actual coolant temperature) is compatible with third-party DAQ systems (e.g., LabVIEW, Delta Tau PMAC) for time-stamped thermal profiling. For GxP-regulated applications, users may implement external audit-trail-capable controllers that record setpoint changes, runtime hours, and fault events—supporting traceability per ALCOA+ principles.

Applications

• Solvent removal and concentration of natural product extracts, polymer solutions, and pharmaceutical intermediates in R&D labs.
• Low-temperature condensation in fractional distillation setups using short-path or Kugelrohr apparatus.
• Coolant supply for cold traps in vacuum manifold systems during Schlenk-line operations.
• Thermal stabilization of photoreaction vessels and cryo-magnetic stirrers requiring sub-ambient jacket cooling.
• Supporting ASTM D2876 (evaporation residue determination) and USP (residual solvents) sample preparation workflows.

FAQ

Can the DL-400 be used with glass condensers rated for −20 °C minimum operating temperature?
Yes—the chiller reliably maintains outlet coolant temperatures down to −15 °C at full flow; however, glycol-water mixtures (e.g., 30% propylene glycol) are recommended below 0 °C to prevent freezing-induced blockage.
Is the reservoir accessible for periodic cleaning or biocide treatment?
Yes—the top-mounted lid features a removable gasket-sealed access port; routine maintenance includes draining, rinsing with deionized water, and refilling with inhibited coolant per manufacturer guidelines.
Does the unit include over-temperature or low-flow shutdown safeguards?
Yes—integrated thermistors trigger compressor cutoff if outlet temperature exceeds 30 °C or if flow sensor detects 10 seconds.
What is the expected service life of the compressor under continuous operation?
Based on accelerated life testing and field data, the compressor exhibits ≥25,000 hours MTBF when operated within specified ambient (10–35 °C) and voltage (220 V ±10%) tolerances.
Are replacement parts such as pump impellers and refrigerant charge kits available through authorized channels?
Yes—Great Wall provides OEM-certified spare parts with documented calibration traceability, including pump assemblies (P/N DL-400-PUMP-01) and R134a recharge kits (P/N DL-400-REF-02).