Startup; Maintenance; Service Kits; Shaft Seal Run-In - Grundfos MQ-Serie Montage- Und Betriebsanleitung

6.4 Startup

Before start-up, the pump must be filled with 4.5 to
5 litres of water to enable it to self-prime. See fig. 10.
The pump is self-priming with a maximum suction lift
of 8 metres.
H O
2
4.5 to 5 l
Fig. 10 Priming the pump
When the pump is started, it will start to self-prime.
When the pump has been primed, it will
automatically change over to normal operation. If the
priming has not been completed within 5 minutes,
the pump will stop automatically and attempt to
restart after 30 minutes. It is possible to reset the
pump manually. See point 2 in the table in section
5.1 Control panel.

7. Maintenance

Under normal operating conditions, the pump is
maintenance-free. However, it is recommended to
keep the pump clean.
Warning
Do not remove the pressure tank from
the pump unless it has been vented
through the air vent valve.
Never touch the electronics unless the
pump has been switched off for at least
5 minutes.
If there is any risk of frost damage, drain the pump
through the drain hole and slacken the union nut on
the discharge pipe. See fig. 11. The pump must be
filled with water before it is started up again.
See fig. 10.
Fig. 11 Draining the pump
12

7.1 Service kits

Service kits are available for the MQ pump.
The service kits consist of the following replaceable
parts:
• shaft seal
• motor
• electronic units
• hydraulic components.

7.2 Shaft seal run-in

The seal faces are lubricated by the pumped liquid,
meaning that there may be a certain amount of
leakage from the shaft seal.
When the pump is started up for the first time, or
when a new shaft seal is installed, a certain run-in
period is required before the leakage is reduced to
an acceptable level. The time required for this
depends on the operating conditions, i.e. every time
the operating conditions change, a new run-in period
will be started.
Under normal conditions, the leaking liquid will
evaporate, which means that no leakage will be
detected.

7.3 Start-up after a long time of inactivity

The end cover incorporates a plug which can be
removed by means of a suitable tool. It is then
possible to free the pump rotor if it has seized up as
a result of inactivity. If the pump has been drained, it
must be filled with water before start-up. See fig. 10.

8. Service

If a pump has been used for a liquid
which is injurious to health or toxic, the
Caution
pump will be classified as
contaminated.
If Grundfos is requested to service the pump,
Grundfos must be contacted with details about the
pumped liquid, etc. before the pump is returned for
service. Otherwise Grundfos can refuse to accept
the pump for service.
Possible costs of returning the pump are paid by the
customer.
However, any application for service (no matter to
whom it may be made) must include details about
the pumped liquid if the pump has been used for
liquids which are injurious to health or toxic.