Johnson Controls A28GJ-33C Two Stage Temperature Control

Product Description

The JOHNSON CONTROLS A28GJ-33C is a two-stage remote bulb temperature control designed for precise setpoint-based switching in HVAC and refrigeration applications. It operates across a setpoint range of 60 to 90 degrees F and features two SPDT (single-pole, double-throw) output circuits, allowing independent control of two stages of heating or cooling equipment. The remote bulb measures 3/8 inch in diameter and 3.5 inches in length, with a 60-inch capillary tube that allows the sensing element to be positioned away from the control body. Licensed HVAC technicians and refrigeration service professionals are the primary installers of this device.

This temperature control is suited for commercial and light commercial HVAC systems, refrigeration equipment, and process temperature applications where two-stage switching is required. The remote bulb configuration makes it appropriate for installations where the sensing point must be physically separated from the control panel or enclosure, such as in walk-in coolers, air handlers, or duct-mounted sensing applications within the 60 to 90 degrees F operating range.

Key Features

• Two-stage control with independent SPDT outputs for sequencing heating or cooling stages
• Setpoint range of 60 to 90 degrees F suits a wide range of HVAC and refrigeration applications
• Remote bulb sensing element: 3/8 inch diameter by 3.5 inches length
• 60-inch capillary tube allows flexible placement of the sensing bulb
• SPDT switching on both stages supports normally open and normally closed circuit configurations

Compatibility

Designed as an OEM-style replacement for two-stage remote bulb temperature controls used in commercial and light commercial HVAC and refrigeration systems requiring a 60 to 90 degrees F setpoint range with dual SPDT outputs.

Installation Notes

Installation should be performed by a licensed HVAC technician or refrigeration mechanic. Disconnect all power to the controlled equipment before wiring or replacing this control. Route the capillary tube carefully to avoid kinking, and secure the remote bulb firmly at the sensing location to ensure accurate temperature response. Follow applicable local codes and the equipment manufacturer's wiring diagram when connecting the SPDT output circuits.

Technical Specifications

• Control Type: Two Stage Remote Bulb Temperature Control
• Setpoint Range: 60 to 90 degrees F
• Outputs: 2 SPDT
• Capillary Length: 60 inches
• Bulb Diameter: 0.375 inches
• Bulb Length: 3.5 inches

Standard Information

• Brand: JOHNSON CONTROLS
• Manufacturer Part Number: A28GJ-33C