Hanuo HH-2 Digital Constant-Temperature Water Bath

Overview

The Hanuo HH-2 Digital Constant-Temperature Water Bath is a precision-engineered thermal control instrument designed for consistent, reproducible heating of samples in laboratory environments. Operating on the principle of convection-based liquid-phase heat transfer, it maintains uniform temperature distribution across its dual-slot stainless steel bath chamber using a high-efficiency tubular heating element and PID-controlled feedback loop. Unlike dry-block heaters or oil baths, water baths provide superior thermal homogeneity and gentle, non-contact heating—critical for temperature-sensitive biological assays, enzyme kinetics, cell culture incubation support, dissolution testing, and calibration of thermometric standards. The HH-2 is engineered for daily operational reliability in QC labs, academic research facilities, and pharmaceutical manufacturing support spaces where stable ambient-to-100 °C thermal conditioning is routinely required.

Key Features

• LED digital display with real-time temperature readout and intuitive push-button interface for setpoint adjustment and status monitoring
• PID temperature controller delivering ±0.5 °C stability across the full 20–100 °C operating range (ambient start)
• Dual independent slots (300 mm × 160 mm × 130 mm each) fabricated from electropolished 304 stainless steel—resistant to corrosion from aqueous buffers, saline solutions, and mild detergents
• Seamless one-piece chamber construction eliminates crevices, simplifies cleaning, and prevents leakage under prolonged immersion
• 600 W heating system with overtemperature cut-off protection and automatic shutdown upon low-water detection
• Low-profile chassis (190 mm height) optimized for benchtop integration beneath fume hoods or adjacent to analytical instruments

Sample Compatibility & Compliance

The HH-2 accommodates standard laboratory glassware including beakers (up to 1000 mL), Erlenmeyer flasks, test tubes, and sample racks used in microbiological media preparation or pharmacopeial dissolution apparatus auxiliary heating. Its stainless steel chamber meets material compatibility requirements for USP , ISO 13485 cleanroom-adjacent use, and CLSI-recommended thermal validation protocols. While not certified as medical device hardware, its thermal performance aligns with ASTM E2251-22 (Standard Specification for Liquid-in-Glass Thermometers) verification conditions and supports IQ/OQ documentation per GMP Annex 15 guidelines. All electrical components conform to IEC 61010-1 safety standards for laboratory equipment.

Software & Data Management

The HH-2 operates as a standalone analog-digital hybrid instrument without embedded software or network connectivity. Temperature logging requires external recording via calibrated data loggers (e.g., Omega OM-DAQPRO-5300) interfaced through its analog 0–5 V output port (optional accessory). For regulated environments, users may integrate the unit into validated workflows by pairing it with 21 CFR Part 11-compliant electronic lab notebooks (ELNs) such as LabArchives or Benchling—documenting setpoints, duration, operator ID, and observed deviations manually or via barcode-scanned batch records. Audit trails must be maintained separately per GLP/GMP requirement since the device lacks built-in user access control or electronic signature capability.

Applications

• Pre-warming reagents and culture media prior to aseptic handling in microbiology and molecular biology labs
• Supporting USP dissolution testing by maintaining sinker basket or paddle assembly temperature stability
• Facilitating controlled enzymatic reactions requiring precise 37 °C or 60 °C incubation windows
• Calibrating liquid-in-glass thermometers and RTDs against NIST-traceable references
• Accelerated stability studies per ICH Q1A(R3) under defined temperature stress conditions
• Thermal equilibration of viscometer spindles, density meters, and refractometer cells

FAQ

What is the maximum recommended water fill level for the HH-2 chamber?
The water level should not exceed 50 mm below the top rim of the chamber to prevent overflow during thermal expansion and ensure proper sensor immersion.
Can the HH-2 be used with corrosive or organic solvents?
No. The chamber is rated for aqueous solutions only. Use of acetone, ethanol, chloroform, or acidic/basic media will compromise stainless steel passivation and void warranty.
Is the temperature sensor externally accessible for third-party calibration?
Yes—the PT100 sensor is mounted flush within the chamber wall and can be verified using a traceable reference thermometer inserted into a dedicated calibration port (M6 thread, depth 25 mm).
Does the HH-2 include a drain valve?
No. Drainage requires manual tilting and siphoning; optional aftermarket drain kits are available from authorized Hanuo distributors.
How frequently should the unit undergo preventive maintenance?
Biannual inspection of heater terminals, grounding continuity, and chamber integrity is recommended—especially in high-humidity or salt-laden environments.