Daikin-McQuay 300060398 Pressure Switch

The Daikin-McQuay 300060398 Pressure Switch is a critical safety component designed for precise low air pressure sensing in commercial HVAC systems. Calibrated to a fixed setpoint of .35" W.C., this differential pressure switch monitors the pressure drop across the blower or burner assembly to ensure proper airflow verification before ignition or operation. Engineered for compatibility with Daikin and McQuay air handlers and rooftop units, it serves as a reliable HVAC inducer pressure switch replacement that prevents equipment operation under hazardous low-flow conditions. The 300060398 pressure sensor features a robust diaphragm construction capable of detecting minute pressure fluctuations, ensuring high-accuracy differential pressure monitoring in demanding environments. For technicians performing HVAC troubleshooting or routine maintenance, this switch provides the exact electrical contact closure required by the system's control board logic, maintaining the integrity of the safety string and preventing premature component failure.

• Fixed Setpoint Precision: Factory-calibrated to .35" W.C. for consistent performance without the need for field adjustment.
• OEM Compatibility: Direct-fit replacement for Daikin-McQuay 300060398, ensuring seamless integration with existing mounting brackets and wiring harnesses.
• Enhanced Reliability: Designed to withstand the thermal cycling and vibration typical of commercial HVAC airflow systems.
• Electrical Integrity: Features high-quality contact points for low-resistance signaling to the furnace or AHU controller.

What causes a .35" W.C. pressure switch to fail to close?
Failure is typically caused by a restricted flue, a blocked venturi, or a malfunctioning inducer motor. If the switch itself is faulty, the internal diaphragm may be ruptured or the contacts may be pitted, requiring a 300060398 replacement.

Can I use a higher setpoint switch if this one is unavailable?
No. Using a switch with a different inches of water column rating will compromise the safety system, either causing nuisance trips or allowing the unit to run with insufficient airflow.

How do I verify the operation of the 300060398 switch?
Use a manometer to measure the actual pressure at the tap. If the pressure exceeds .35" W.C. and the switch remains open (check with a multimeter for continuity), the component is defective.

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.