303.02.0048 Compatible 4-Circuit Protection Valve

What does a 4-circuit protection valve do?

This 4-circuit protection valve serves as a critical component within the pneumatic brake system of heavy commercial vehicles. It functions by distributing supply pressure to four independent circuits, including the front and rear brakes, while providing essential isolation if a pressure loss occurs in any single circuit. This ensures the continued safety and stability of the vehicle's braking performance under heavy loads.

Compatible vehicles and engines

This part is compatible with Iveco trucks and is designed to meet the rigorous demands of heavy-duty service environments. It is engineered to work seamlessly within pneumatic systems, ensuring reliable pressure regulation and circuit protection during operation.

Installation and maintenance

Technical installation requires attention to the specific port sizes: Port 1 features an M22x1.5 thread, while Ports 21 through 24 utilize M16x1.5 threads. The component operates at a standard 13 BAR with a maximum pressure capacity of 20 BAR, ensuring stability during high-pressure cycles. Technicians should verify all connection points to ensure secure fitment.

System performance and troubleshooting

Regular inspection of the valve helps prevent air leaks and ensures that the opening and closing pressures—specifically the 6.6 BAR opening and 4.5 BAR closing thresholds—function correctly to maintain system integrity.

OE cross-reference

303.02.0048 (4-circuit protection valve) is the equivalent of the Iveco and Knorr-Bremse OE numbers. This part directly replaces Iveco OE number 42530050. It also replaces Knorr-Bremse OE number AE4642.