A421AEC-02C Johnson Controls Temperature Control

Overview

The Johnson Controls A421AEC-02C is a line-voltage Type 4X electronic temperature control designed for single-stage heating or cooling applications. It features a watertight, corrosion-resistant NEMA 4X/IP66 enclosure suitable for surface-mount installations and includes an A99BB-200C PTC temperature sensor with a 6.6-foot cable.

Features

• Bright, adjustable backlit LCD screen displaying temperature, parameters, and system status
• Simple three-button touchpad interface for basic and advanced programming menus
• Adjustable On and Off temperature setpoints for direct or reverse control actions without repositioning jumpers
• High and low temperature setpoint adjustment stops to restrict unauthorized user adjustments
• Adjustable anti-short cycle delay to protect compressors and inductive equipment from short cycling
• Temperature setback/offset control capability activated via an external switch or timer connected to the binary input

Specifications

• Supply Voltage: 120/240 VAC, 50/60 Hz
• Output Relay: 1 SPDT dry-contact relay
• Temperature Control Range: -40°F to 212°F (-40°C to 100°C)
• Differential Range: 1°F to 30°F
• Power Consumption: Maximum 1.8 VA
• Enclosure Rating: NEMA 4X / IP66 watertight thermoplastic
• Included Sensor: A99BB-200C PTC sensor with 6.6 ft (2.0 m) lead

Applications

The A421AEC-02C is ideal for commercial and industrial single-stage temperature control applications. It is commonly used in commercial refrigeration equipment like walk-in coolers, reach-in boxes, and display cases, as well as in boiler, chiller, fan, and damper control systems requiring robust environmental protection.