Hanuo HNW-S-4 Precision Digital Timer-Controlled Constant-Temperature Water Bath

Overview

The Hanuo HNW-S-4 Precision Digital Timer-Controlled Constant-Temperature Water Bath is an engineered solution for laboratories requiring stable, repeatable thermal environments across a wide range of routine and research-grade applications. Operating on the principle of convective heat transfer via water as a uniform thermal medium, this unit maintains precise temperature control within a range of ambient to 100 °C—ideal for enzyme assays, cell culture incubation, sample thawing, reagent warming, and dissolution testing. Its dual-column, four-well configuration provides scalable capacity without compromising thermal homogeneity or operational stability. Designed for integration into ISO/IEC 17025-accredited labs and GLP-compliant workflows, the HNW-S-4 meets foundational requirements for traceable temperature control in analytical and quality assurance settings.

Key Features

• Microprocessor-based PID temperature controller delivering ≤ ±0.5 °C fluctuation and ≤ ±1 °C uniformity across the entire bath volume
• High-contrast backlit LCD display showing real-time setpoint, actual temperature, elapsed time, and remaining timer duration
• Programmable digital timer supporting intervals from 1 minute to 99 hours 59 minutes, with automatic shutdown upon completion
• Over-temperature safety cutoff with audible and visual alarm to prevent sample degradation or equipment damage
• Robust construction: 304 stainless steel inner bath resistant to corrosion from aqueous buffers, saline solutions, and mild detergents; cold-rolled steel outer casing with epoxy-polyester powder coating for chemical and abrasion resistance
• Modular design enabling optional integration of magnetic stirrers (sold separately) for homogeneous mixing during temperature-controlled reactions
• Low-noise heating elements with optimized thermal distribution to minimize localized hot spots and ensure reproducible results across all wells

Sample Compatibility & Compliance

The HNW-S-4 accommodates standard laboratory glassware—including test tubes (up to 25 mm diameter), Erlenmeyer flasks (up to 500 mL), beakers (up to 1000 mL), and cuvettes—within its 300 mm × 300 mm × 130 mm working chamber. Its non-reactive stainless steel bath surface ensures compatibility with phosphate-buffered saline (PBS), Tris-HCl, sucrose gradients, and other biologically relevant media. The unit complies with IEC 61010-1:2010 for electrical safety in laboratory equipment and supports documentation required for FDA 21 CFR Part 11–aligned environments when paired with validated calibration and maintenance logs. While not intrinsically certified for hazardous locations, it is suitable for use in general-purpose lab spaces under standard HVAC and electrical infrastructure per EN 60335-1.

Software & Data Management

The HNW-S-4 operates as a standalone instrument with embedded firmware—no external PC software is required for basic operation. However, its digital interface supports manual logging of setpoints, durations, and observed deviations for inclusion in lab notebooks or electronic quality records (eQMS). For facilities implementing paperless workflows, the device’s timer and temperature readouts can be manually transcribed into LIMS or ELN platforms compliant with ALCOA+ data integrity principles. Calibration certificates (traceable to NIST or equivalent national metrology institutes) are available upon request and should be renewed annually or per internal SOPs. Audit trails for temperature excursions or timer resets are maintained in non-volatile memory for up to 100 event cycles.

Applications

• Enzyme kinetics studies requiring strict thermal consistency between replicate reactions
• Pre-incubation of microbial cultures prior to plating or spectrophotometric analysis
• Controlled thawing of cryopreserved cell lines to minimize thermal shock
• Dissolution testing of pharmaceutical dosage forms per USP
• Standardization of viscosity measurements using capillary or rotational viscometers
• Hybridization protocols in molecular biology where precise denaturation/annealing temperatures are critical
• Calibration of thermocouples, RTDs, and infrared thermometers against a stable liquid-phase reference

FAQ

What is the maximum recommended water level for optimal thermal performance?
Fill the bath chamber to approximately 20–30 mm below the top rim to ensure full immersion of samples while preventing overflow during expansion at elevated temperatures.
Can the HNW-S-4 be used with organic solvents such as ethanol or acetone?
No. The unit is designed exclusively for aqueous media. Organic solvents may degrade seals, corrode stainless steel over time, and pose fire hazards due to flashpoint limitations.
Is external temperature calibration supported via RS232 or USB?
The HNW-S-4 does not feature digital communication ports. Temperature verification must be performed using a calibrated reference thermometer placed centrally in the bath.
How often should the water bath be cleaned and disinfected?
Daily removal of debris and weekly cleaning with mild detergent and deionized water is recommended. Bi-weekly disinfection with 70% ethanol or 0.1% sodium hypochlorite solution helps prevent biofilm formation in high-use environments.
Does the unit include a drain valve for easy water replacement?
Yes, a front-mounted brass drain valve allows rapid, controlled emptying without tilting or lifting the unit.