Refrigerated heating circulator HRHC series

for high temperatures

Description
HRHC series -45°C ~ +180°C Refrigerating Heating Circulators by Labfreez Instruments are dynamic temperature control systems designed for precise heating, cooling and recirculation. Suitable for reactors, autoclaves, pilot plants, scale-up operations, double-wall reactors, advanced-flow reactors, distillation systems, material testing, combinatorial chemistry, semiconductor processes and vacuum chambers.

Thermostat Application
HRHC units (hermetic refrigerating & heating circulators) connect to reactor systems, autoclaves, pilot systems, mini-plant setups and scale-up processes to provide controlled jacket or material temperature and continuous recirculation.

Thermostat Advantages & Functions

• Hermetic closed-loop circulation for high temperature accuracy and extended working fluid life.
• Very wide working temperature ranges across models; continuous control without frequent heat transfer fluid changes.
• Intelligent PID control with feed-forward for stable setpoint tracking.
• High process stability and reproducibility.
• Plate heat exchanger and optimized heating circuit for improved heat transfer rates.
• Cooling capacity scalable by model (typ. 0.5 kW up to 500 kW depending on configuration).
• Optional TFT touch displays (4", 7", 10") with graphical trend view.
• Comprehensive alarms and safety functions.
• Rapid cooldown capability from high temperatures.
• Optional remote-control software with communication up to 200 m.
• Compact footprint for laboratory and pilot installations.

Thermostat Structure design
Fully closed piping with a high-efficiency plate heat exchanger minimizes required heat transfer medium while enabling fast temperature changes. The expansion vessel is limited to 60°C.

• Only medium in expansion vessel contacts air (vessel ≤60°C), reducing oxidation/volatilization risk.
• No volatilization of heat transfer medium at high temperature within operating ranges.
• No need to change medium for continuous control across very wide ranges (examples: -80°C~190°C, -70°C~220°C, -88°C~170°C, -55°C~250°C, -30°C~300°C) without pressure rise.

Thermostat Display function

• Process control temperatures display.
• Expansion vessel liquid level.
• Refrigeration system status.
• Heater status.
• Circulation pump status.
• Temperature control mode selection (material vs. heat transfer medium).
• Settable upper/lower temperature limits and jacket/material differential.
• Low-liquid alarm.
• Compressor manual/automatic selection.
• Temperature curve display with zoom and export.
• Recipe/program set and display; alarm notes.

Thermostat Principle of process control
Two-loop PID architecture (master and slave) with feed-forward PV. Master loop output plus feed-forward compose the subordinate setpoint, minimizing lag and overshoot and ensuring accurate temperature gradients.

Thermostat High repeatability of results control
High-accuracy PID and closed-loop design provide stable, repeatable temperature control for process validation and scale-up.

Circulation Pump
High-temperature-resistant magnetic drive pumps or leak-free shield-driven pumps reduce leakage risk while delivering low-noise, high-flow recirculation (model dependent up to ~20 L/min, pressures up to ~2 bar).

Electronic expansion valve
Systems use electronic expansion valves (e.g., Emerson) with precise stepping (0–750 steps/min) for accurate refrigerant metering and improved control accuracy.

Configuration software (Optional)

• Communication distance up to 200 m.
• Remote setpoint and parameter setting.
• Real-time control screen and temperature curve recording/export.
• Program selection and alarm recording.

Safety protection
Multiple safety and self-diagnosis features: phase-sequence protection, leakage protection, refrigeration high/low pressure/voltage protection, pump/compressor overload protection, high/low liquid level alarms, dual over-temperature protections, circulation line shut protection and other thermal/overload protections.

Connecting Pipe (items)

• Fluorine rubber hose | -30~200°C | Φ12×16, Φ16×22, Φ20×26
• Metal insulated pipe | -60~250°C | DN15, DN20, DN25, M24×1.5, M30×1.5, M38×1.5

Date interface & software (standard)

• Inputs: PT100 temperature sensor(s).
• USB data export.
• RS485 (MODBUS RTU).
• Alarm contact output.

Heat conduction medium
Selection of suitable heat transfer medium is essential. Labfreez Instruments supplies media in 10 L, 25 L, 30 L and 200 L packaging; choose according to operating temperature and system design.

Thermostat Optional

• 4–20 mA temperature measurement input.
• 4–20 mA temperature setpoint input.
• Ethernet interface.
• RS232 (MODBUS) interface.
• Computer operating software (requires Ethernet).
• External control box with touch-screen display.

Common Specifications

• Control mode: Feed-forward PID, PLC control.
• Temperature control: Independent control of material and circulation liquid temperatures.
• Program memory: 20 programs, 45 segments per program.
• Communication: MODBUS RTU via RS485.
• Temperature sensors: PT100 for circulation medium and raw material (3 points); optional 4–20 mA.
• Control panel: 7" color touch screen (curve display & record).
• Safety: Self-diagnosis, overload and thermal protections, high-pressure switch, relays.
• Closed loop: Fully closed system; no oil mist at high temperature, minimal moisture absorption at low temperature, stable pressure across wide ranges; automatic replenishment for heat transfer medium.

Specifications (excerpt for models shown)

• Model: HRHC-320 | Temperature range: -30°C~180°C | Accuracy: ±1°C | Heating power: 2 kW | Cooling capacity (example): 1.5 kW (180°C / 50°C / 0°C)
• Model: HRHC-420W | Temperature range: -45°C~180°C | Accuracy: ±1°C | Heating power: 2 kW | Cooling capacity (example): 1.8 kW (180°C / 50°C / 0°C)
• Model: HRHC-430W | Temperature range: -45°C~180°C | Accuracy: ±1°C | Heating power: 3 kW | Cooling capacity (example): 3 kW (180°C / 50°C / 0°C)
• Circulation pump (examples): Max 10–20 L/min, 0.8–2 BAR; Compressors: Embraco or model-dependent; Expansion valve: Danfoss; Refrigerant (example): R-404A.
• Connection size: DN15 or M24×1.5; Water-cooled types W: specific flow rates (example: 450–550 L/H at 20°C).
• Dimensions / Weight / Power: model-dependent (see spec table).

Typical Application
Temperature control for glass reactors, multi-reactor setups, laboratory pilot plants, reaction vessels and other processes requiring precise heating/cooling and recirculation control.

Technical characteristics / specifications

• Brand: Labfreez Instruments
• Series name: HRHC series
• Operating temperature (examples): from -45°C up to +180°C (model dependent)
• Temperature accuracy: ±1°C (typical)
• Heating power: 2–3 kW typical (model dependent)
• Cooling capacity: varies by model and temperature point (see table)
• Circulation pump: magnetic drive or shield-driven, up to ~20 L/min (model dependent)
• Compressor: Embraco or model-dependent
• Expansion valve: Danfoss electronic expansion valve
• Interfaces: PT100, USB, RS485 (MODBUS), alarm contact; optional Ethernet/RS232/4–20 mA
• Control: Feed-forward PID with PLC; recipe/program support (20 programs, 45 segments each)
• Safety: Multi-level alarms and protections (overheat, low liquid, compressor/pump protections)
• Housing material: Stainless steel SUS304