Yoyi LHG-9140A Vertical Precision Forced-Air Constant-Temperature Drying Oven

Overview

The Yoyi LHG-9140A is a vertically oriented, microprocessor-controlled forced-air drying oven engineered for precision thermal processing in regulated laboratory and industrial quality control environments. It operates on the principle of convective heat transfer via a balanced, rear-mounted air circulation system—designed to maintain stable, uniform temperature distribution across the working chamber. Unlike natural convection ovens, this model integrates an optimized wind tunnel architecture with adjustable airflow dynamics, enabling consistent thermal profiles essential for applications requiring reproducible drying, baking, sterilization, or thermal stabilization of samples. Its design conforms to GB/T 30435–2013, the Chinese national standard for electrically heated forced-air drying ovens, and serves as a functional equivalent to ISO 17025-compliant thermal equipment when operated under documented validation protocols.

Key Features

• Intelligent microcomputer PID temperature controller with dual-stage overtemperature protection: primary control loop + independent mechanical safety limiter (optional)
• Large-view double-layer tempered glass observation window with high-temperature silicone gasket seal—enabling real-time visual monitoring without thermal disturbance
• Electrostatically coated cold-rolled steel exterior and electropolished stainless-steel interior chamber (AISI 304 grade), resistant to corrosion and easy to decontaminate
• Modular shelf system with tool-free height adjustment; standard configuration includes two removable stainless-steel trays
• Automated exhaust/intake ducting with passive vapor management—eliminates manual vent adjustment and reduces condensation buildup during prolonged low-temperature drying cycles
• Power-fail recovery function: retains setpoint parameters and resumes operation upon power restoration, minimizing experimental interruption
• LCD menu-driven interface displaying set temperature, actual chamber temperature, elapsed time, and remaining hold duration simultaneously

Sample Compatibility & Compliance

The LHG-9140A accommodates a broad range of sample types—including biological specimens, polymer films, pharmaceutical excipients, ceramic precursors, electronic components, and moisture-sensitive reagents—within its 136 L working volume. Its temperature stability (±1.0°C fluctuation) and uniformity (±2.5% deviation at 100°C, empty chamber) meet typical requirements for ASTM D1654 (coating drying evaluation), USP (sterile processing validation support), and ISO 5725-based repeatability criteria. While not certified to IEC 61010-1 or UL 61010B out-of-the-box, the unit can be integrated into GLP/GMP workflows when accompanied by user-performed IQ/OQ documentation and periodic calibration against NIST-traceable reference thermometers.

Software & Data Management

The standard configuration supports optional RS485 serial communication (Modbus RTU protocol) for integration with laboratory information management systems (LIMS) or SCADA platforms. When paired with the optional data logging software package, users may configure time-stamped temperature recording intervals, generate CSV-formatted audit trails, and export trend graphs compatible with FDA 21 CFR Part 11–aligned electronic record retention policies. An embedded thermal printer option provides hard-copy output of temperature logs and alarm events—serving as supplementary evidence during internal audits or regulatory inspections. All firmware operations retain timestamped event logs for critical status changes (e.g., door open/close, overtemperature activation, power cycle).

Applications

This drying oven is routinely deployed in academic research laboratories for solvent removal from thin-film coatings and nanoparticle suspensions; in QC labs for residual moisture determination per USP ; in biotech facilities for low-heat desiccation of lyophilized intermediates; and in electronics manufacturing for pre-bake treatment of PCB substrates prior to conformal coating. Its extended upper limit (250°C) permits controlled depolymerization studies, catalyst activation, and ash content preparation per AOAC 923.03. The inert gas inlet port (optional) facilitates oxygen-sensitive processes such as metal oxide annealing or anaerobic polymer crosslinking—when used with externally regulated nitrogen or argon supply lines and calibrated rotameter flow control.

FAQ

What is the maximum operating temperature and does it support ramp-soak profiling?
The LHG-9140A has a maximum operating temperature of 250°C. Ramp-soak functionality is not included in the base controller but can be added via the optional multi-segment programmable temperature controller accessory (model-specific, priced separately).
Is the chamber volume verified per ISO 17025 calibration standards?
Chamber volume is a geometric specification (450 × 550 × 550 mm), not a calibrated parameter. Users performing gravimetric or thermographic validation should conduct their own chamber mapping per ISO/IEC 17025 Clause 5.10.
Can this oven be used for sterilization of medical devices?
It is not classified as a Class II medical device sterilizer and lacks validation documentation for ISO 17665 or EN 285. It may serve as a drying step post-steam sterilization but must not replace validated sterilization cycles.
Does the unit include a built-in calibration certificate?
No factory-issued calibration certificate is provided. Users are responsible for initial verification using traceable reference sensors and establishing routine calibration intervals per organizational SOPs.
Are replacement shelves and gaskets available as spare parts?
Yes—stainless-steel trays (part #LHG-SH-01), silicone door seals (part #LHG-GSK-02), and air filter elements (part #LHG-FLT-03) are stocked and ship globally within 5 business days.