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Valves

Troubleshooting

Diagnosing and resolving common issues with HPzenAi valves — solenoid, hydraulic, and pressure control.

Valve Not Opening When Commanded​

Cause: The relay channel is not delivering 12V DC to the solenoid coil, or the solenoid coil has failed.

How to Fix​

  • In the app, open the relay controller tile and verify the channel status shows 'Open' after tapping the control — if the channel shows 'Open' but the valve stays closed, the wiring or valve is the issue.
  • Measure voltage at the relay channel COM and NO terminals with a multimeter — you should read 12V DC when the channel is energised.
  • Listen for the solenoid click when the relay switches — no click means the relay is not switching or the solenoid coil is burnt.
  • Disconnect the valve cable and measure resistance across the solenoid coil terminals — a healthy coil reads 20–60 Ω. An open circuit (OL) indicates a burnt coil.
  • Check that the relay controller has 12V DC power at its input — no power means no channels can switch.
  • Replace the solenoid coil or valve body if the coil reads open circuit.

Valve Not Closing Fully — Continuous Drip or Seep​

Cause: Debris lodged in the valve diaphragm or seat, or a worn diaphragm that no longer seals correctly.

How to Fix​

  • Isolate the upstream water supply and depressurise the line before opening the valve body.
  • Remove the solenoid coil and unscrew the valve bonnet to expose the diaphragm.
  • Inspect the diaphragm for small tears, holes, or deformation — replace the diaphragm if damaged.
  • Clear any grit, sand, or debris from the valve seat and diaphragm orifice using clean water.
  • Reassemble the valve and restore water supply — confirm the valve seals fully with the relay channel off.
  • If leakage continues after diaphragm cleaning and replacement, replace the valve body.

Valve Chattering or Buzzing When Open​

Cause: Supply water pressure is below the valve's minimum operating pressure, or there is electrical interference on the 12V line.

How to Fix​

  • Verify the upstream water pressure is within the valve's operating range — solenoid valves require a minimum of 0.3 bar to hold the diaphragm open silently.
  • Check the 12V DC supply voltage at the relay controller output — voltage below 10V can cause solenoid chatter.
  • Inspect the 12V power adapter for overload — if other channels are simultaneously switching high-current loads, voltage may sag.
  • Ensure the valve cable run is not routed alongside mains power cables — electromagnetic interference can cause coil buzz.
  • If chattering persists at correct voltage and pressure, the solenoid coil may be aging — replace the coil.

Scheduled Irrigation Not Running​

Cause: The schedule was not saved correctly to the relay controller, or the controller lost its schedule during a firmware update or power failure.

How to Fix​

  • Open the relay controller in the app, tap Schedules, and confirm the schedule is listed with the correct time, duration, and days.
  • Check the schedule is enabled — a greyed-out or toggled-off schedule will not run.
  • Verify the relay controller has power and is online (green LED or 'Connected' status in app).
  • Confirm the correct channel is assigned to the schedule — a schedule on channel 2 will not open the valve on channel 3.
  • Delete and recreate the schedule if the stored data appears corrupted — the controller will accept the new schedule immediately.
  • Schedules run on the controller's internal clock — ensure the controller time zone is set correctly under Device Settings → Time.

Guided Help Center

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Relay Controller Not Visible in the App​

Cause: The relay controller is not connected to the gateway via RS485, or the gateway has not yet completed an RS485 scan.

How to Fix​

  • Verify the relay controller has 12V DC power — check the power LED on the controller.
  • Confirm RS485 A and B wires are not swapped — reversed polarity prevents detection.
  • In the app, go to Gateway → RS485 Scan to manually trigger a new device search.
  • Check that the relay controller RS485 address is unique — if two devices share address 1, neither will be detected reliably.
  • Use a short test cable directly between the gateway and controller to rule out a cable fault before testing longer runs.
  • If using Wi-Fi mode (stand-alone), confirm the controller is in setup mode (blue flashing LED) and follow the Wi-Fi Setup guide.

Hydraulic Valve Not Actuating​

Cause: The pilot solenoid is not receiving power, or the line pressure is outside the hydraulic valve's operating range.

How to Fix​

  • Confirm the pilot solenoid coil is wired to COM and NO on the relay channel — not to the main valve body terminals.
  • Measure 12V DC across the pilot solenoid terminals when the relay channel is energised.
  • Verify the upstream line pressure is between 0.5 and 16 bar — hydraulic valves will not actuate outside this range.
  • Inspect the pilot solenoid strainer for debris blockage — clean the strainer screen if clogged.
  • Ensure the hydraulic valve body is installed with the correct flow direction — check the arrow on the valve body.
  • If the pilot solenoid clicks but the main valve body does not open, the main valve diaphragm or actuator requires service.

Manual Override Stuck — Valve Remains Open or Closed​

Cause: A manual override command was sent from the app and the next scheduled event has not yet fired to return the valve to automatic control.

How to Fix​

  • Open the relay controller tile in the app and check for a 'Manual' badge on the affected channel.
  • Tap the channel and tap Resume Schedule to return the valve to automatic schedule control.
  • If no schedule is assigned, manually close the valve by tapping the Close button in the app.
  • Check that the app is connected to the internet — manual resume commands require connectivity.
  • If the channel badge does not update after tapping Resume, power-cycle the relay controller and re-check the channel state.

Valve Opens Correctly But App Shows Wrong State​

Cause: The relay controller status has not synced to the cloud, typically due to a brief internet outage at the gateway.

How to Fix​

  • Pull down to refresh the device tile in the app — this triggers an immediate status poll.
  • Check the gateway is online: Main Menu → Gateway — the status indicator should show 'Connected'.
  • If the gateway went offline during a valve operation, the status may be stale — the gateway will sync the current state once reconnected.
  • Restart the gateway from the app: Gateway → Settings → Restart, then re-check the valve channel state.
  • If the problem recurs, check the gateway Wi-Fi signal strength and consider a Wi-Fi repeater or SIM-enabled gateway.

Guided Help Center

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Pressure Reducing Valve Not Holding Set Pressure​

Cause: The PRV adjustment screw setting has drifted, or the internal spring and seat require service.

How to Fix​

  • Install a downstream pressure gauge close to the PRV to measure actual downstream pressure.
  • Turn the PRV adjustment screw clockwise to increase downstream pressure, counter-clockwise to decrease.
  • Make small adjustments (quarter turns) and allow 30 seconds for pressure to stabilise before re-reading.
  • If the PRV cannot hold pressure within the expected range after adjustment, inspect the seat and diaphragm for wear or debris.
  • Flush the line upstream of the PRV to remove grit that may be lodging under the valve seat.
  • Replace the PRV if the internal spring has lost tension or the seat is visibly eroded.

Valve Offline After Power Interruption​

Cause: The relay controller did not automatically re-establish its connection after power was restored.

How to Fix​

  • Wait 2–3 minutes after power restoration — the relay controller and gateway reconnect automatically.
  • If the controller remains offline after 5 minutes, check the 12V DC supply voltage at the controller input.
  • Restart the gateway from the app if the gateway itself shows offline.
  • Any schedules stored on the controller continue to run locally even during gateway outages — valve operation is not affected by internet loss.
  • If the controller is back online but schedules show the wrong next-run time, re-check the controller time zone under Device Settings → Time.