Hanuo HH-420 Triple-Function Constant-Temperature Water Bath
| Brand | Hanuo |
|---|---|
| Model | HH-420 |
| Type | Triple-Function Water Bath (Water Bath Pot / Temperature-Controlled Water Tank / Boiling Sterilization Unit) |
| Dimensions (L×W×H) | 420×180×200 mm |
| Temperature Range | Ambient to 100 °C |
| Heating Power | 1000 W |
| Temperature Control Accuracy | ±0.5 °C |
| Construction Material | Stainless Steel (AISI 304) |
| Display | Digital LED |
| Control Mode | Automatic PID Temperature Regulation |
| Origin | Shanghai, China |
Overview
The Hanuo HH-420 Triple-Function Constant-Temperature Water Bath is an engineered laboratory thermal platform designed for precise, stable, and reproducible temperature control across three primary operational modes: standard water bath heating, constant-temperature immersion incubation, and boiling-based sterilization of laboratory instruments. It operates on the principle of convective heat transfer through a thermally uniform water medium, ensuring minimal thermal gradients (<0.3 °C across working volume under steady-state conditions). Unlike single-purpose units, the HH-420 integrates functional versatility without compromising thermal stability or safety integrity—making it suitable for routine QC testing, sample preparation in molecular biology workflows, solvent evaporation in analytical chemistry, and low-risk instrument decontamination in teaching labs and small-scale research facilities. Its stainless steel tank and insulated chamber provide long-term resistance to corrosion from aqueous reagents and repeated thermal cycling.
Key Features
- Triple-mode operation: configurable as a water bath pot (for beaker/flask immersion), temperature-controlled water tank (for rack-mounted sample holders), and boiling sterilizer (with adjustable boil duration timer logic)
- AISI 304 stainless steel inner tank with seamless welding and electropolished finish for enhanced corrosion resistance and ease of cleaning
- Digital PID temperature controller with LED display, offering real-time setpoint and actual temperature readout in 0.1 °C resolution
- Over-temperature cut-off protection (mechanical backup thermostat) and dry-run prevention circuitry to mitigate heater damage during low-water conditions
- Front-accessible water level indicator and drain valve for rapid maintenance and fluid exchange
- Low electromagnetic interference (EMI) design compliant with IEC 61326-1 for co-location with sensitive instrumentation
Sample Compatibility & Compliance
The HH-420 accommodates standard laboratory glassware including 50–1000 mL beakers, Erlenmeyer flasks, test tube racks (up to 16 mm diameter × 20 positions), and sterilization baskets (optional accessory). Its temperature uniformity profile meets ASTM E1112-22 requirements for Class II water baths used in biological sample conditioning. While not certified for ISO 13485 medical device sterilization or FDA 510(k) clearance, the unit supports GLP-aligned documentation practices via manual logbook integration. It complies with CE marking directives (2014/30/EU EMC Directive and 2014/35/EU LVD Directive) and conforms to RoHS 2011/65/EU restrictions on hazardous substances.
Software & Data Management
The HH-420 operates as a standalone analog-digital hybrid system with no embedded firmware or network interface. Temperature data logging requires external recording via 4–20 mA or 0–5 V analog output (available upon request with optional signal module). For audit-trail compliance in regulated environments, users may integrate the unit into validated laboratory information management systems (LIMS) using third-party USB-to-RTD adapters and time-stamped CSV export tools. All control parameters—including setpoint, ramp rate, hold time, and alarm thresholds—are manually configured and non-volatile upon power loss.
Applications
- Controlled evaporation of organic solvents during HPLC sample prep and extract concentration
- Pre-incubation of enzymatic reaction mixtures prior to kinetic assays (e.g., ELISA, PCR master mix equilibration)
- Thermal conditioning of viscosity standards and calibration oils per ASTM D445
- Boiling sterilization of reusable pipette tips, forceps, and glass spreaders in microbiology teaching labs
- Temperature stabilization of pH electrodes and dissolved oxygen probes during field calibration
- Supporting USP environmental monitoring protocols for low-risk compounding areas (non-sterile auxiliary use only)
FAQ
What is the maximum recommended water fill volume for the HH-420?
The working volume is approximately 12 L at optimal operating level (15 mm below rim); exceeding this may impair circulation uniformity and trigger low-water alarms.
Can the HH-420 maintain temperature stability during ambient fluctuations?
Yes—the unit achieves ±0.5 °C accuracy over 8-hour continuous operation at 37 °C under ISO 17025 lab conditions (23 ±2 °C ambient, <60% RH).
Is the stainless steel tank suitable for saltwater or acidic solutions?
AISI 304 resists mild chlorides and dilute acetic/citric acids; however, prolonged exposure to >0.5% NaCl or pH <3 solutions is not recommended without post-use neutralization and rinsing.
Does the HH-420 support external temperature probe input for chamber monitoring?
No—internal PT100 sensor only; external probe integration requires OEM modification and voids warranty.
What maintenance intervals are recommended for long-term reliability?
Biannual descaling with 5% citric acid solution and annual verification of thermal cut-off function using calibrated reference thermometer (NIST-traceable).
