Scientz GH-15A High-Precision Circulating Bath (Heating & Cooling)

Overview

The Scientz GH-15A High-Precision Circulating Bath is an engineered thermal management system designed for laboratory and industrial applications requiring stringent temperature control across a broad operational range. Operating on the principle of forced convection via a high-efficiency circulation pump, the GH-15A maintains uniform thermal distribution within its stainless-steel bath chamber while simultaneously supporting external temperature regulation through dual-mode (heating and refrigeration) thermoelectric and compressor-based thermal exchange. Its core architecture integrates a microprocessor-controlled PID algorithm with real-time feedback from a calibrated platinum resistance thermometer (PT100), enabling dynamic compensation for ambient fluctuations, load changes, and thermal inertia. Unlike basic immersion baths, the GH-15A functions as both a self-contained precision bath and a programmable external heat transfer source—making it suitable for calibration traceability, material property testing, and process simulation where thermal stability at the sub-0.01 °C level is critical.

Key Features

• High-stability temperature control with programmable setpoint resolution of 0.01 °C and long-term stability of ±0.005 °C (at 25 °C, no external load)
• Dual circulation mode: internal recirculation for bath homogeneity; external loop capability with adjustable flow rate (0–20 L/min) for integration with calorimeters, viscometers, or custom test rigs
• Environmentally compliant refrigerant (R-134a or equivalent) and energy-efficient compressor design meeting IEC 61000-3-2 harmonic emission standards
• Intelligent power management: configurable auto-restart behavior after power interruption, preserving user-defined parameters and operational state
• Programmable timer function with up to 999-hour duration; automatic shutdown upon completion for unattended operation
• Corrosion-resistant 304 stainless-steel bath tank (300 × 240 × 200 mm internal dimensions) rated for use with water, silicone oil, and low-viscosity heat-transfer fluids up to 200 °C

Sample Compatibility & Compliance

The GH-15A accommodates a wide range of sample vessels—including glass Dewar flasks, metal calibration blocks, and jacketed reactors—without compromising thermal uniformity. Its external circulation port supports standard 1/4″–3/8″ tubing connections and is compatible with pressure-rated closed-loop systems. From a regulatory standpoint, the instrument meets CE marking requirements for electromagnetic compatibility (EMC Directive 2014/30/EU) and low-voltage safety (LVD Directive 2014/35/EU). While not inherently 21 CFR Part 11-compliant, its logging-capable controller supports audit-trail-ready data export when interfaced with validated third-party software—facilitating GLP/GMP-aligned calibration workflows per ISO/IEC 17025 and ASTM E2877-22 (Standard Guide for Calibration of Temperature-Controlled Baths).

Software & Data Management

The GH-15A features an embedded 4.3-inch TFT-LCD interface with intuitive menu navigation and real-time display of setpoint, actual temperature, pump status, and error codes. RS232 and optional USB-to-serial interfaces enable bidirectional communication with host PCs running Windows-based configuration tools. Data logging is supported at user-selectable intervals (1 s to 60 min), with timestamped CSV files exportable for post-processing in MATLAB, Python (Pandas), or LIMS platforms. Firmware updates are performed via SD card, ensuring field-upgradability without hardware modification. For regulated environments, optional validation documentation packages—including IQ/OQ protocols and traceable calibration certificates—are available upon request.

Applications

• Primary and secondary calibration of liquid-in-glass thermometers, RTDs, thermistors, and infrared sensors per ISO 17025-accredited procedures
• Thermal conditioning of reference materials prior to DSC, TGA, or rheological analysis
• Stabilization of optical components (e.g., laser diodes, interferometer stages) requiring sub-millikelvin thermal drift control
• Supporting ASTM D2857 (FTIR spectroscopy), ASTM D445 (kinematic viscosity), and USP (thermal analysis of pharmaceuticals)
• Process validation in biopharmaceutical manufacturing, including incubator and autoclave sensor verification
• Material testing under controlled thermal stress: coefficient of thermal expansion (CTE), thermal conductivity, and phase transition studies

FAQ

What is the maximum allowable fluid temperature for external circulation?
The GH-15A supports external loop operation up to 200 °C when using thermally stable silicone oils or specialized heat-transfer fluids rated for continuous service at that temperature.
Does the unit support remote monitoring via Ethernet or Wi-Fi?
No native Ethernet or Wi-Fi interface is included; however, RS232-to-Ethernet gateways may be deployed for network integration in facility-wide SCADA environments.
Is the bath tank drainable for maintenance or fluid replacement?
Yes—a front-mounted quick-release drain valve enables complete fluid evacuation without disassembly.
Can the GH-15A maintain stability at 5 °C in ambient conditions above 35 °C?
Yes, provided adequate ventilation space (≥15 cm clearance on all sides) and ambient humidity below 80% RH; performance conforms to specifications under ISO 17025 environmental classification Class II.
Are calibration certificates provided with shipment?
A factory-issued calibration report (traceable to NIM, China) is included; UKAS or NIST-traceable certificates are available as optional add-ons.