Debris might be jammed in the controller's internal check valve. Disassemble and flush with clean water.
If you encounter operational issues, consult this troubleshooting index before contacting technical support. Device Will Not Turn On (No LED Light) Faulty power connection or bad outlet.
For advanced users, the Zenox ZPC-EP1 likely offers further configuration options. Information on these topics can be found in the official manual or by searching online support forums:
4x 12-bit resolution channels (0-10V or 4-20mA configurable)
1.1 kW (1.5 HP) to 1.5 kW (2.0 HP) dependent on specific regional sub-models Maximum Working Pressure: 10 bar (145 PSI)