High pressure filter with differential pressure controlled coldstart valve. The filterhead contains a cold-start valve which guarantees under all operating conditions that the hydraulic system is provided only with filtered fluid. When the differential pressure rises above the opening pressure of the cold-start valve (e.g. due to high cold-start viscosity or due to a not serviced filter element), a partial flow is returned to the tank via the filter heads tank connection.
The system is provided only with filter fluids
A reduction of the flow rate indicates an outstanding filter element change
Performance curves as per leaflet Pi 420 respectively Pi 4000