Filter valve assembly

A filter assembly comprising:

• a manifold having a fluid inlet and a fluid outlet;
• a filter housing;
• a filter medium within the filter housing, the filter medium defining an inner filter chamber and defining an outer filter chamber between the filter medium and the filter housing,
• the filter housing being removably attached to the manifold so as to provide a fluid flow path from the inlet into the inner filter chamber, through the filter medium into the outer chamber and out of the outlet;
• and
• a valve assembly mounted inside the manifold, the valve assembly comprising:
• a shut off valve piston and a shut off valve spring arranged in engagement with the valve piston to bias the valve piston into a first position;
• an adaptor ring located between the shut off valve piston and the filter housing and provided with an annular outlet seal;
• wherein the shut off valve piston is provided with a radially extending flange and an inner piston wall configured such that as the filter housing is being detached from the manifold, the shut off valve spring expands to move the shut off valve piston to a shut off position whereby the piston flange is in sealing engagement with the adaptor ring and the outlet seal, and the inner piston wall is in sealing engagement with inlet seals such that flow from the fluid inlet and the fluid outlet is shut off from entering the filter housing;
• a bypass channel between the fluid inlet and the fluid outlet;
• and
• a disk spring positioned across the bypass channel such that, in its default state, the disk spring extends across the bypass channel to prevent flow from the fluid inlet to the fluid outlet via the bypass channel and wherein, when the pressure differential across the disk spring exceeds a predetermined threshold, the disk spring deforms to open the bypass channel and allow the flow of fluid from the fluid inlet to the fluid outlet via the bypass channel;
• wherein the shut off valve spring is located in a cavity outside of the path of fluid flow through the assembly.