Grundfos MQ 3-45 User Manual

17
English (US)
15. Fault finding chart
If the pump does not start when the fault has been corrected, contact your pump supplier or Grundfos for
further information.
Fault Cause Remedy
1. The pump does
not start.
a) Insufficient water. Check the water supply/suction pipe.
b) Overheating due to excessive liquid
temperature (above +95 °F / +35 °C).
Supply cold liquid to the pump.
c) Overheating due to seized-up/
choked-up pump.
Contact your pump supplier.
d) Too low or too high supply voltage. Check the supply voltage and correct the
fault, if possible.
e) No electricity supply. Connect the electricity supply.
f) No water consumption. Open a tap. Check that the height
between the top point of the discharge
pipe and the pump does not exceed 50 ft.
g) Shaft is blocked. Rotate the shaft as described in
11.3 Start-up after a long period of
inactivity.
h) Pump is in alarm condition. Reset the pump by means of the on/off
button. See point 2 in the table of
section 10.1 Control panel.
2. The pump does
not stop.
a) Existing pipework is leaking or
defective.
Repair the pipework.
b) Non-return valve is blocked or
missing.
Clean the valve or fit a new non-return
valve.
3. The pump cuts
out during
operation.
a) Dry running. Check the water supply/suction pipe.
b) Overheating due to excessive liquid
temperature (above +95 °F / +35 °C).
Supply cold liquid to the pump.
c) Overheating caused by:
– high ambient temperature
(> 113 °F / 45 °C)
– overloaded motor
– seized-up motor/pump.
Contact your pump supplier.
d) Too low supply voltage. Check the supply voltage and correct the
fault, if possible.
4. The pump starts
and stops too
frequently.
a) Leakage in suction pipe or air in
water.
Check the water and the supply/suction
pipe.
b) Too low or too high pressure in
pressure tank.
Check the pressure in the pressure tank.
See section 7. Operating conditions.
5. The pump gives
electric shocks.
a) Defective ground connection. Connect the ground connection to the
pump in accordance with local
regulations.
6. The pump starts
when no water is
consumed.
a) Internal non-return valve is
defective, or the existing pipework
is leaking or defective.
Clean the valve or fit a new one.

Grundfos MQ 3-45 Specifications

General

Power consumption	1000 W
Maximum head	45 m
Maximum flow rate	3 m³/h
Protection class	IP54
Weight	13 kg
Maximum liquid temperature	35 °C
Maximum operating pressure	7.5 bar
Pumped liquid	Clean water
Liquid temperature range	0 - 35 °C
Maximum ambient temperature	45 °C
Supply voltage	220-240 V
Rated power - P2	0.75 kW
Mains frequency	50/60 Hz
Rated current	4.5 A
Enclosure class	IP54
Inlet connection	1 inch
Outlet connection	1 inch
Power supply	220-240 V, 50/60 Hz
Pump type	Centrifugal
Built-in pressure tank	Yes
Approvals	CE
Material	Stainless steel