9. Malfunctions, causes, and remedies
EN
86
9.4 Dual Line control unit - Commissioning malfunctions
Malfunction Cause Remedy
Motor fails to start
when the operating
voltage is applied
o Motor incorrectly connected
o Pump timing not parameterized
• Check that motor connection is wired correctly
• Inspect pump timing as described in Chapter 6.3.1
Pump does not
switch off on
reaching minimum
fill level
o Fill level switch NC contact/NO-contact incorrectly
configured
• Check connection on fill level switch
No pressure
build-up
o Relief valve connected incorrectly
o Directional solenoid valves for zone(s) incorrectly
connected
o Pressure switch PT not/incorrectly connected
• Check that connections are wired correctly
No pressure relief
o Reversing valve not/incorrectly connected
o Directional solenoid valves for zone(s) not/incorrectly
connected
o Pressure switch PT not/incorrectly connected
o Relief valve does not work
• Inspect relief valve, replace if necessary
o Holding time too short (only with 2/2 directional
solenoid valves)
• Extend holding time