Tianfeng TF-HX-5A Precision Refrigerated/Heating Circulating Bath

Overview

The Tianfeng TF-HX-5A Precision Refrigerated/Heating Circulating Bath is a compact, self-contained temperature control system engineered for high-stability thermal management in laboratory and research environments. Utilizing a dual-mode thermodynamic architecture—integrating an air-cooled hermetic refrigeration compressor with resistive heating elements—the unit delivers precise, bidirectional temperature regulation across a wide operational range of −10 °C to 99 °C. Its core function relies on forced convection via an integrated circulation pump, enabling both internal bath homogenization and external fluid transfer through standardized fittings (e.g., 1/4″ NPT or quick-connect ports). This design supports two primary operational modes: (1) direct immersion-based temperature control within the 5-liter stainless-steel bath chamber, and (2) remote temperature conditioning of auxiliary equipment—such as rotary evaporators, viscometers, electrophoresis systems, cryogenic medical devices, or vacuum pumps—via closed-loop external circulation. The system’s thermal stability of ±0.1 °C (at setpoint, under static load conditions) meets requirements for reproducible physical property measurements, kinetic studies, and calibration traceability in regulated workflows.

Key Features

• High-precision PID temperature control with digital touchscreen interface and dual LED display (temperature + timer)
• Stainless-steel inner tank (304 grade) for corrosion resistance, chemical compatibility, and ease of cleaning
• Dual-circulation capability: independent internal recirculation for bath uniformity and external port for secondary thermal field establishment
• Imported air-cooled hermetic compressor delivering rapid cooldown from ambient to −10 °C and stable low-temperature hold
• Advanced evaporator geometry optimized for large-volume heat exchange efficiency and spatial temperature uniformity
• Programmable functions including delayed start, timed shutdown, and real-time deviation monitoring
• Comprehensive safety suite: over-temperature cutoff, differential-temperature alarm, and dry-run protection
• Compact footprint (430 × 285 × 575 mm) suitable for benchtop integration in space-constrained labs

Sample Compatibility & Compliance

The TF-HX-5A accommodates aqueous, ethylene glycol–water mixtures, silicone oils, and other non-corrosive heat-transfer fluids compatible with stainless-steel wetted parts. It is not intended for use with halogenated solvents, strong acids/bases, or flammable media without prior validation. As a Class I electrical appliance per IEC 61010-1, it complies with general laboratory safety standards for protected operator environments. While not inherently 21 CFR Part 11–compliant, its digital logging interface supports integration with validated third-party data acquisition systems for GLP/GMP-aligned applications. The unit is manufactured under an ISO 9001:2000–certified quality management system, ensuring consistent process control during design, assembly, and functional testing. Documentation includes factory calibration reports (traceable to national metrology institutes), CE-marking documentation (for EU export variants), and RoHS-compliant material declarations.

Software & Data Management

The TF-HX-5A operates via embedded firmware with no proprietary PC software dependency. All configuration, monitoring, and alarm history are managed locally through its front-panel interface. Temperature setpoints, ramp rates, hold durations, and event logs (e.g., alarm triggers, power cycles) are retained in non-volatile memory. For laboratories requiring centralized monitoring or audit-ready records, the unit provides analog output (0–10 V or 4–20 mA) proportional to bath temperature—enabling connection to PLCs, SCADA systems, or validated electronic lab notebooks (ELNs). Optional RS-485 Modbus RTU communication modules (sold separately) permit remote parameter adjustment and real-time telemetry in multi-unit installations, supporting compliance with FDA 21 CFR Part 11 when deployed within validated network architectures.

Applications

• Thermal conditioning of analytical instruments: cooling condensers in rotary evaporators, stabilizing detector temperatures in HPLC autosamplers, and maintaining constant bath temperature for capillary electrophoresis systems
• Material property testing: viscosity measurement using rotational viscometers, thermal expansion coefficient determination, and phase transition analysis in polymer solutions
• Biological sample preservation: controlled hypothermia protocols for tissue culture media, enzyme activity assays at defined temperatures, and cold-chain validation for diagnostic reagents
• Chemical synthesis support: exothermic reaction quenching, crystallization kinetics studies, and reflux temperature maintenance in small-scale batch reactors
• Calibration traceability: serving as a stable reference source for thermometer verification (per ASTM E77 and ISO 17025 requirements) and thermal sensor validation
• Medical device support: powering therapeutic cooling blankets, cryoablation probe chillers, and MRI coil temperature stabilization loops

FAQ

What types of heat-transfer fluids are compatible with the TF-HX-5A?
Deionized water, 30–50% ethylene glycol/water mixtures, and low-viscosity silicone oils (e.g., DC200 series) are recommended. Avoid chlorinated, brominated, or highly acidic/basic fluids.
Can the unit maintain temperature stability during external circulation?
Yes—when properly sized tubing and flow rates are used (<2 L/min recommended), the system maintains ±0.15 °C stability at the external outlet under steady-state conditions.
Is the bath volume adjustable or expandable?
No—the 5 L capacity is fixed by the stainless-steel reservoir geometry. Larger volumes require higher-capacity models (e.g., TF-HX-10A or TF-HX-20A).
Does the unit include a built-in filtration system for the circulating fluid?
It features a coarse mesh inlet filter to prevent particulate ingress but does not include active filtration; users must pre-filter fluids for sensitive downstream applications.
What is the typical cooldown time from 25 °C to −10 °C?
Approximately 45–55 minutes under no-load conditions with deionized water; times vary with fluid type, volume, and ambient temperature.
Is remote monitoring possible without optional hardware?
Basic status indicators (temperature, alarm state) are visible via the front panel only; RS-485 or analog output modules are required for remote readout or control.