Multi-circuit protection valve assembly and air processing unit

A multi-circuit protection valve assembly for a pressurized air system of a commercial vehicle, comprising

• an air inlet for receiving compressed air;
• at least two main outlets for discharging the received compressed air to at least two consumer circuits that are each coupled to one of the respective main outlets;
• at least two main supply lines each being flow-connected or flow-connectable to said air inlet and each being flow-connected or flow-connectable to at least one of said main outlets for distributing the compressed air to the at least two main outlets;
• and
• at least two main overflow valves each being located in one of said main supply lines for protecting the main outlet flow-connected or flow-connectable to the respective main supply line containing the main overflow valve,
• wherein the air inlet, the main outlets, the main supply lines and the main overflow valves are attached to or are integrated into a main housing of the multi-circuit protection valve assembly,
• wherein the multi-circuit protection valve assembly further comprises an extension part having
• an extension inlet for receiving compressed air;
• at least one extension outlet for discharging the received compressed air to a consumer circuit that is coupled to the respective extension outlet;
• an extension line being flow-connected or flow-connectable to said extension inlet and to the at least one extension outlet;
• and
• an extension overflow valve being located in the extension line for protecting the at least one extension outlet flow-connected or flow-connectable to the extension line containing the extension overflow valve,
• each being attached or integrated into an extension housing, wherein the extension housing is detachably fixed to the main housing such that the extension inlet is flow-connected to an auxiliary outlet in the main housing, wherein the auxiliary outlet is flow-connected or flow-connectable to said air inlet in the main housing,
• wherein:
• the extension housing is detachably fixed to the main housing by a hollow screw having a cavity, wherein said hollow screw passes through the extension housing and is screwed into the auxiliary outlet:
• such that the extension housing is clamped to the main housing, and
• such that compressed air discharged through the auxiliary outlet can be conducted through the cavity inside the hollow screw to the extension overflow valve and the at least one extension outlet.