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Problem
Possible cause
Solution
High viscosity of medium
Reduce viscosity, as far as pos‐
sible
Air introduction in the suction con‐
nections
Check connections and accesso‐
ries for air tightness
Vibrations on pumps and pipelines The pipes are not correctly fas‐
tened
Fasten pipes correctly (e.g. wall
brackets)
Pump speed too high
Reduce pump speed
Insufficient nominal width of the
pipes
Increase nominal width
Pump base plate loose
Fasten base plate
Pulsation dampers insufficient or
missing
Install pulsation dampers on suc‐
tion and / or discharge side.
Short operational lifetime of the
hoses
Chemical exposure
Check the compatibility of the
hose with the liquid being con‐
veyed, the cleaning fluid and the
lubricant
High pump speed
Reduce pump speed
High conveying temperature
Reduce product temperature
High operating pressure
Reduce operating pressure
Pump cavitations
Check the suction conditions
Pump hose pulled into the pump
housing
High inlet pressure (> 3 bar)
Reduce inlet pressure
Pump hose filled with deposits
Clean or replace the pump hose
Holder (pressure flange) insuffi‐
ciently tightened
Re-tighten holder (pressure
flange)
The pump does not start up
Insufficient motor performance
Check motor and replace if neces‐
sary
Insufficient output from frequency
converter
The frequency converter must
match the motor
Check voltage. Start occurs at
minimum 10 Hz
Blockage in the pump
Check if the suction or discharge
side is blocked. Rectify blockage
Maintenance, repair, malfunctions, disposal and spare parts
35