Wilo Multivert MVIS 408-1/16/K/3-400-50-2, Installation And Operating Instructions Manual

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English
10. Faults, causes and remedies
WARNING! Danger due to electrical voltage!
Dangers from electricity must be ruled out.
The pump must be voltage-free before com-
mencing electrical work and secured against
unintended reactivation.
WARNING! Risk of burns!
If the water temperature and the system pres-
sure are high, close the stop valve on the suction
side and on the pressure side.
The pump must cool down first.
Fault Cause Remedy
The pump is not running
No power supply Check fuse protection, wiring and
connections
Motor protection has interrupted the
power supply
Avoid overloading the motor
The pump runs but does not reach its
duty point
Incorrect direction of rotation Check the direction of rotation and
correct as necessary
Pump components are blocked by
foreign objects
Check the pump and clean it
Air inclusion in the pump Seal the suction port
Suction line too narrow Install a larger suction line
The stop valve is not sufficiently open Fully open the stop valve
The pump does not pump evenly
Air in the pump Vent the pump and ensure that the
suction line is sealed.
If necessary, start the pump for 20
to 30 s. Open the venting screw so that
the air can escape. Close the venting
screw and repeat the procedure as often
as required
The pump vibrates or is loud
Foreign object in the pump Remove the foreign object
The pump is not properly attached to
the ground
Tighten the anchor screws
Bearing damaged Contact Wilo customer service
The motor has overheated, motor
protection has been activated
One phase is interrupted Check fuse protection, wiring and
connections
Fluid temperature too high Maximum fluid temperature
Foreign object in the pump Remove the foreign object
Bearing damaged Contact Wilo customer service
If the fault cannot be remedied,
contact Wilo customer service.
WILO SE 01/2020