LabTech RH40-25A Refrigerated & Heated Circulating Chiller

Overview

The LabTech RH40-25A Refrigerated & Heated Circulating Chiller is a precision temperature control instrument engineered for stable thermal management of external equipment—including spectrophotometers, rotary evaporators, calorimeters, and reaction jackets—as well as for direct sample immersion in open baths. It operates on a closed-loop thermodynamic principle: a high-efficiency refrigeration circuit (R134a or R290 refrigerant-based, depending on regional compliance) works in tandem with a PID-regulated electric heating system to deliver bidirectional temperature control across a broad operational range. Unlike single-function chillers or heaters, the RH40-25A dynamically switches between cooling and heating modes based on setpoint deviation, minimizing overshoot and ensuring thermal equilibrium within demanding experimental protocols. Its compact footprint and robust thermal architecture make it suitable for benchtop integration in ISO 17025-accredited laboratories and R&D facilities where space, reliability, and reproducibility are critical.

Key Features

• Seamless one-piece stainless steel bath tank—electropolished finish, corrosion-resistant, and compliant with USP Class VI material standards for laboratory-grade fluid contact surfaces.
• Intelligent dual-mode PID temperature control algorithm with adaptive tuning, achieving typical temperature stability of ±0.05 °C under steady-state conditions (verified per ASTM E2654-21 guidelines for thermal stability testing).
• Independent internal recirculation (for bath self-stabilization) and external circulation (for external device cooling/heating), selected via front-panel toggle—no tool required.
• Integrated safety interlocks: real-time monitoring of bath temperature extremes, liquid level detection via capacitive sensor, and automatic shutdown upon fault detection.
• LCD interface with backlight and English-language menu navigation; displays setpoint, actual bath temperature, pump speed (%), and active alarm status.
• RS485 serial interface compliant with Modbus RTU protocol, enabling integration into centralized lab automation systems and LIMS platforms with audit-trail-capable data logging.

Sample Compatibility & Compliance

The RH40-25A supports aqueous, ethylene glycol–water mixtures (up to 50 vol%), and silicone oil media (viscosity ≤ 50 cSt) for extended low-temperature operation. Its open-bath configuration accommodates standard laboratory glassware (e.g., 1–5 L jacketed reactors, cuvette holders, and optical mounts) without modification. The unit is designed and tested to meet IEC 61010-1:2010 (Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use) and complies with electromagnetic compatibility (EMC) requirements per EN 61326-1:2013. While not certified for medical device use, its firmware architecture supports 21 CFR Part 11–aligned electronic record integrity when deployed with validated third-party data acquisition software.

Software & Data Management

The chiller does not include embedded PC software but provides full command-line access via RS485 for custom SCADA integration. Lab managers may deploy industry-standard platforms—including LabVIEW™, MATLAB® Data Acquisition Toolbox, or Python-based PySerial scripts—to log temperature profiles, trigger alarms, and synchronize with HPLC or DSC instrument timelines. All parameter changes and alarm events are timestamped and retained in non-volatile memory for post-run forensic review—a requirement under GLP Annex 11 and ISO/IEC 17025:2017 clause 7.7.2.

Applications

• Temperature stabilization of laser sources and interferometric optical tables in metrology labs.
• Controlled-rate cooling/heating cycles for polymer crystallization studies (ASTM D3418).
• Thermal conditioning of enzymatic assay buffers in molecular biology workflows.
• Heat removal from high-power LED test fixtures during photometric characterization.
• Preconditioning of food emulsions prior to rheological analysis using coaxial cylinder geometries.

FAQ

What is the maximum external flow rate supported at full pressure head?
The RH40-25A delivers up to 18 L/min at 0.3 bar backpressure, optimized for tubing IDs ≥ 8 mm and total loop lengths ≤ 10 m.
Can this unit operate continuously at –40 °C ambient temperature?
Yes—the chiller is rated for continuous operation in environments between 10–32 °C ambient, with condenser airflow maintained per manufacturer-specified clearance requirements.
Is the bath volume customizable?
The standard RH40-25A features a fixed 25 L working volume; custom bath volumes are available under OEM agreement with LabTech Beijing R&D Center.
Does the unit support calibration traceability to NIST standards?
While the built-in sensor is factory-calibrated against reference PRTs (Pt100, Class A), end-user calibration verification using external traceable thermometers (e.g., Fluke 1523 with 700-series probe) is recommended per ISO/IEC 17025 calibration intervals.
How is firmware updated?
Firmware updates require authorized service technician intervention via proprietary diagnostic port; no field-upgrade capability is provided to preserve regulatory integrity.