LINES GP-EXHAUST COMBUSTION 3617260 - Caterpillar

Illustration 1 g00277838
Pressure protection valve (1) Supply passage (2) Valve (3) Delivery passage
Illustration 2 g00650225
Location of pressure protection valve for the air systemThe pressure protection valve is located in the compartment that is behind the cab. Remove the cover in order to access the compartment.The pressure protection valve prevents a complete loss of air pressure in the event of a failure in either the secondary air system or any accessory device.All air flow from the primary air circuit to the secondary air circuit flows through the pressure protection valve. Air will not flow through the pressure protection valve until the air pressure at supply passage (1) reaches the valve opening pressure. When the air pressure reaches the valve opening pressure, valve (2) moves in order to allow air to flow through the pressure protection valve to delivery passage (3). The pressure protection valve closes when the air pressure reaches the valve closing pressure.For specific values of the valve opening pressure and the valve closing pressure, refer to Specifications, "Pressure Protection Valve (Air System)" for the Air System and Brakes.