The AEC TDV Series is a positive/negative pressure water temperature control unit designed for injection molding and industrial process cooling applications where mold cooling circuit leaks present a serious production problem. The defining capability of the TDV is its positive/negative pressure operation, which uses a liquid venturi to draw cooling water through the mold under controlled negative pressure. In negative pressure mode, water does not leak out of small mold stress cracks—it is drawn inward, allowing production to continue without immediate mold repair while protecting the mold from water damage and maintaining cooling performance.

Microprocessor PID Control with LED Readout

• Off-the-shelf PID Controller: The integrated microprocessor-based PID temperature controller provides precise automatic temperature regulation by activating the immersion heater or the cooling water solenoid as required. Both Process and Set Value temperatures are displayed on an easy-to-read LED panel.
• Graphic Control Panel: A graphic control panel with indicating and warning status lights provides at-a-glance system status, alerting operators to conditions requiring attention before they escalate into process interruptions.
• Temperature Range: The unit operates from 32 °F to 180 °F (0 °C to 82 °C), covering the process water temperature requirements for most injection molding and plastics processing applications.

Positive/Negative Pressure Technology

• Liquid Venturi Negative Pressure Mode: A manually-operated 3-way valve switches the cooling circuit from conventional positive pressure to negative pressure. In negative pressure mode, a liquid venturi generates a controlled vacuum that draws water through the mold cooling channels from a cooling tower, chiller, or city water supply. If a mold has developed small stress cracks, the negative pressure ensures that water is drawn into the mold rather than leaking outward onto the molded part or the machine bed.
• Standard Positive Pressure Mode: For molds without leakage issues, the unit operates as a conventional positive pressure temperature control unit, circulating temperature-controlled water through the mold at the desired setpoint.
• Open Reservoir Design: The open reservoir is vented to atmosphere, simplifying water level management and allowing for natural deaeration of the circulating water.

Immersion Heater, Pump & Cooling Components

• Incoloy™ Immersion Heater: A single stage Incoloy™ immersion heater (available in 9 kW or 12 kW ratings) provides rapid, efficient heat transfer directly to the process water. IEC-rated mechanical contactors ensure reliable electrical switching under the high-duty cycle typical of injection molding applications.
• Centrifugal Pump: The centrifugal pump circulates water through the mold at consistent flow and pressure, with the pump housing, impeller, heater tube, and piping covered by a lifetime warranty.
• 1/4" Cooling Solenoid Valve: A 1/4" solenoid valve (Cv=0.85) controls cooling water injection. Manually-operated 3-way valve allows quick changeover between positive and negative pressure modes without tools or re-plumbing.

Integrated Safety Systems & Monitoring

• Hi/Low Level Sensor: A hi/low water level sensor with a 3/8" makeup solenoid valve automatically maintains the correct water level, protecting the heater from dry-fire conditions and ensuring continuous reliable operation.
• Low Supply Water Pressure Switch: Monitors the incoming cooling water supply pressure and shuts down the unit if pressure falls below the minimum required for proper cooling, preventing mold overheating during water supply failures.
• 150 psi (10.3 bar) Pressure Relief Valve: Protects the closed cooling circuit from over-pressurization conditions, ensuring safe operation in systems with restrictive mold channels.
• High Temperature Safety Switch (Optional): An optional high temperature safety switch provides an independent over-temperature cutout for applications where process safety requires redundant protection beyond the primary PID controller.

Warranty & Optional Features

• Warranty Coverage: 1-year warranty on parts and labor at factory; 5-year warranty on the controller; lifetime warranty on the pump housing, impeller, heater tube, and piping.
• Optional Features Available: Remote control enclosure, remote thermocouple (10 ft), high/low temperature audible and visual alarm with strobe, crash cool mode (holds cooling solenoid on while turning heater off), pressure gauge, power cord (10 ft, no plug), external communications (RS-232C, RS-422, RS-485), NEMA 1 or NEMA 3R disconnect with fuses, modulating valve (various sizes and Cv ratings), and rubber feet in lieu of casters. Contact AEC for available voltages (208/230/460 V 60 Hz, 380/415 V 50 Hz) and de-rated heater and pump capacities for non-standard configurations.

Applications

• Injection molding mold temperature control with leaking cooling circuits
• Plastics processing requiring precise water temperature management
• Process cooling applications where mold micro-cracks cannot be immediately repaired
• Industrial manufacturing environments where process water temperature stability is critical to product quality