Dorman 904-627 HVAC Pressure Switch

Reliable HVAC Pressure Switch for Select GM Vehicles

The Dorman 904-627 HVAC Pressure Switch is designed to maintain optimal air conditioning system performance in specific Cadillac, Chevrolet, and GMC models. Engineered for vehicles using R134a refrigerant, this pressure switch ensures accurate pressure monitoring and system protection.

• Operates at 12 volts with a 15-amp amperage rating
• Compatible with R134a refrigerant systems
• Pressure limits: closes at 290 psi, opens at 475 psi, max reading 600 psi
• Durable plastic housing with a green oval female connector
• Screw-on mount type with 3/8-16 thread diameter
• Two male pin terminals for secure electrical connection
• Specific fit for Cadillac Escalade, Chevrolet Tahoe, GMC Yukon, and related models

Product Details and Specifications

The Dorman 904-627 HVAC Pressure Switch is a vehicle-specific component designed to monitor refrigerant pressure within the air conditioning system. It features a plastic housing and a green oval-shaped female connector with two male pin terminals, ensuring a reliable electrical connection. The switch operates at 12 volts and is rated for 15 amps, suitable for standard automotive HVAC systems using R134a refrigerant. It activates by closing at 290 psi and opens at 475 psi, with a maximum pressure reading of 600 psi, providing precise control to protect the A/C compressor and system components from pressure extremes.

Compatible Vehicles and Applications

This pressure switch is compatible with a range of GM trucks and SUVs, including:

• Cadillac Escalade and Escalade EXT
• Chevrolet Avalanche 1500, Blazer, C1500, C1500 Suburban, Suburban 1500, Tahoe
• GMC K1500, K1500 Suburban, Yukon, Yukon XL 1500

Designed specifically for these models, the Dorman 904-627 ensures proper fit and function within the factory HVAC system.

Common Issues Addressed by the HVAC Pressure Switch

• Prevents compressor damage due to abnormal refrigerant pressure
• Helps maintain consistent air conditioning performance
• Protects against system overpressure and underpressure conditions
• Eliminates intermittent A/C operation caused by faulty pressure sensing
• Ensures accurate pressure readings for system diagnostics

Installation Notes and Tips

The Dorman 904-627 pressure switch mounts via a screw-on method using a 3/8-16 thread diameter. Ensure the system is depressurized before removal or installation to avoid refrigerant loss or injury. The green oval female connector with two male pin terminals should be securely connected to the vehicle’s wiring harness. No mounting bracket is included, so use the existing factory mounting point. Verify compatibility with your specific vehicle model and refrigerant type before installation.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The 904-627 HVAC Pressure Switch undergoes rigorous quality control to ensure reliable operation within specified pressure limits. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in material and workmanship. Consult product documentation or your parts provider for exact warranty terms.