Johnson Controls A25AN-1 Temperature Control

The Johnson Controls A25AN-1 is a heavy-duty warm air limit control designed for high-limit protection in forced air heating systems. This mechanical temperature control features a single-pole single-throw (SPST) switch configuration that opens on temperature rise, providing a critical safety cutoff to prevent furnace overheating. With a setpoint range of 25 to 215°F and a manual reset mechanism, the A25AN-1 ensures that equipment remains offline until a technician can investigate the cause of the high-limit trip. Engineered for versatility, it operates on 24 to 277Vac circuits and includes a knob range adjuster for precise field calibration. This unit is the direct functional equivalent to the A25AN-1C, maintaining the same 125°F high-limit factory setting and rod and tube sensing element design. For contractors managing HVAC safety controls, this high limit switch offers reliable, snap-acting contact performance in demanding industrial and commercial thermal applications.

• Field Adjustability: The integrated knob range adjuster allows for rapid setpoint modifications across the 25 to 215°F spectrum.
• Fail-Safe Operation: The manual reset feature prevents automatic cycling under fault conditions, protecting the heat exchanger and blower motor.
• Universal Compatibility: Supports multiple voltages from 24V to 277V, making it a standard stock item for diverse furnace and air handler platforms.
• Robust Sensing: Utilizes a durable rod and tube element for accurate ambient temperature detection within the ductwork.
• Direct Replacement: Fully interchangeable with Johnson Controls A25AN-1C models for seamless maintenance and repair workflows.

Common Questions

What is the difference between A25AN-1 and A25AN-1C?
These models are technically identical in specifications, mounting, and performance; the "C" suffix typically denotes bulk packaging or specific distributor labeling but does not affect the mechanical temperature control functions.

How do I reset the A25AN-1 after a high-limit trip?
This is a manual reset control. Once the warm air limit has cooled below the setpoint, you must physically depress the reset button to close the SPST circuit and restore power to the heating system.

Can this be used as a fan shroud or circulator controller?
No, the A25AN-1 is an Open High limit control. For fan cycling, you would require a control that closes on temperature rise (Open Low) to activate the blower once the plenum reaches the desired temperature.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.