Dorman 904-623 HVAC Pressure Switch

Reliable HVAC Pressure Switch for Buick, Cadillac, and Oldsmobile

The Dorman 904-623 HVAC Pressure Switch is designed to maintain optimal air conditioning system performance in select Buick, Cadillac, and Oldsmobile models. Engineered for specific fitment, this pressure switch ensures accurate pressure monitoring and system protection.

• Operates at 13 volts with a 4-amp amperage rating
• Compatible with R134a refrigerant systems
• Pressure limits: closes at 10 psi and opens at 20 psi
• Maximum pressure reading up to 350 psi
• Durable metal housing with screw-on mount type and 7/16-20 thread diameter
• Features a black circular female connector with two male blade terminals
• Designed specifically for Buick Brougham, Cadillac DeVille, Eldorado, Fleetwood, Reatta, Riviera, Seville, and Oldsmobile Toronado

Technical Details and Compatibility

The Dorman 904-623 HVAC Pressure Switch is built to meet the precise requirements of certain GM luxury and full-size vehicles. Its metal housing provides durability under high-pressure conditions, while the screw-on mount ensures secure installation. The switch operates within a pressure range that protects the A/C system by opening and closing at preset limits, preventing damage from excessive pressure. The black circular connector with two blade terminals facilitates a reliable electrical connection compatible with the vehicle’s wiring harness.

Common Applications and Problem Resolution

• Prevents compressor damage by monitoring refrigerant pressure
• Stops A/C system operation during low or high pressure conditions
• Helps resolve intermittent or no cooling issues related to pressure switch failure
• Eliminates electrical connection problems with secure blade terminals
• Maintains system safety by accurately triggering pressure limits

Installation Notes and Tips

Installation requires removing the old pressure switch and screwing on the Dorman 904-623 switch using the 7/16-20 thread. Ensure the electrical connector matches the vehicle’s female circular connector and that the blade terminals align properly. No mounting bracket is included, so use the existing mounting point. Verify system pressure and refrigerant type (R134a) before installation to ensure compatibility.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM specifications for fit, form, and function. The 904-623 HVAC Pressure Switch undergoes rigorous testing to ensure reliable operation under specified voltage and pressure conditions. This part is backed by Dorman’s standard warranty, providing confidence in its durability and performance for Buick, Cadillac, and Oldsmobile applications.