DRETOP TDK-24R Refrigerated Circulating Constant-Temperature Bath

Overview

The DRETOP TDK-24R Refrigerated Constant-Temperature Bath is a precision-engineered laboratory thermal management system designed for applications requiring stable, controllable temperature environments between 15 °C and 70 °C. Unlike standard heating-only water baths, the TDK-24R integrates a compressor-based refrigeration module with resistive heating elements to enable bidirectional thermal control—critical for experiments demanding both sub-ambient stabilization and elevated temperature maintenance. Its operation relies on direct immersion of a sealed heating element and high-sensitivity Pt100 temperature sensor within the bath medium, ensuring real-time feedback and minimal thermal lag. The unit employs microprocessor-based PID control architecture to dynamically modulate power delivery, achieving ±0.3 °C stability under steady-state conditions—a specification aligned with ASTM E1112 and ISO/IEC 17025 requirements for temperature-controlled test environments. Intended for use with distilled or Type III purified water (to prevent scaling and corrosion), the bath serves as a foundational thermal platform in analytical chemistry, biological incubation support, material conditioning, and calibration traceability workflows.

Key Features

• Integrated refrigeration-heating system enabling precise bidirectional temperature control from 15 °C to 70 °C
• Microprocessor-driven PID controller with auto-tuning capability and LED digital display (0.1 °C resolution)
• Stainless steel 304 inner tank and lid—corrosion-resistant, non-porous, and compliant with GLP cleaning protocols
• Electrostatically coated steel exterior housing for mechanical durability and chemical resistance
• Multi-layer insulated bath chamber minimizing thermal loss and enhancing energy efficiency
• Integrated dry-run protection via level sensor—automatically disables heating if fluid volume falls below operational threshold
• Over-temperature alarm and cut-off function preventing thermal overshoot and safeguarding samples
• Power-loss memory retention: restores previously set parameters upon re-energization

Sample Compatibility & Compliance

The TDK-24R accommodates standard laboratory glassware—including beakers, flasks, reaction vessels, and jacketed reactors—within its 24 L working volume (internal dimensions: approx. 500 × 350 × 140 mm). Its non-circulating design is optimized for static immersion applications where convective mixing is unnecessary or undesirable (e.g., low-viscosity solvent equilibration, enzymatic assay pre-incubation, or reference standard conditioning). The bath complies with IEC 61010-1:2010 safety standards for electrical equipment used in laboratory environments. While not equipped with built-in RS485 or Ethernet interfaces, optional communication modules are available for integration into centralized lab infrastructure supporting FDA 21 CFR Part 11–compliant audit trails when paired with validated third-party software.

Software & Data Management

The base configuration operates via front-panel controls with no embedded data logging. However, optional accessories include a 30-segment programmable temperature controller for time-dependent thermal profiles (e.g., ramp-hold-cool sequences) and an RS485 interface kit compatible with Modbus RTU protocol. When deployed with validated external acquisition systems, the TDK-24R supports full traceability of setpoints, actual temperatures, and alarm events—enabling compliance with GMP documentation requirements for QC laboratories performing USP thermal validation or ISO 17025 method verification. All firmware updates and calibration logs must be manually archived per institutional SOPs.

Applications

• Pre-conditioning of reagents and standards prior to HPLC, GC, or spectrophotometric analysis
• Temperature-controlled solubility studies and crystallization kinetics in pharmaceutical development
• Support heating/cooling for jacketed bioreactors and small-scale chemical synthesis reactors
• Calibration of thermocouples, RTDs, and infrared thermometers against NIST-traceable references
• Thermal stress testing of polymers, adhesives, and encapsulants in materials science labs
• Incubation support for microbial culture media preparation and viability assays
• Controlled evaporation and concentration of volatile organic extracts in environmental testing

FAQ

Does the TDK-24R include a circulation pump?
No—the TDK-24R is a non-circulating bath. For applications requiring uniform temperature distribution across large or irregularly shaped loads, consider the TDK-XB54 or TDK-B30 series with integrated magnetic drive pumps.
What coolant medium is recommended?
Distilled water or Type III purified water is required. Tap water introduces mineral deposits that impair heater longevity, reduce thermal response fidelity, and risk sensor drift.
Is the unit suitable for long-term unattended operation?
Yes—provided the bath remains filled above the minimum level line and ambient room temperature stays within 18–28 °C. The dry-run protection and over-temperature cutoff ensure fail-safe operation.
Can this bath achieve temperatures below 15 °C?
No—the refrigeration module is rated for a minimum setpoint of 15 °C. For sub-zero applications, consult DRETOP’s DK4-30-II low-temperature circulating chiller series.
What maintenance intervals are recommended?
Monthly visual inspection of tank integrity and sensor mounting; quarterly descaling using 5% citric acid solution if purified water is not consistently used; annual verification of temperature accuracy using a calibrated reference thermometer per ISO/IEC 17025 Clause 6.5.