Maintenance; Service Kits; Shaft Seal Run-In; Start-Up After A Long Period Of Inactivity - Grundfos MQ Serie Manual Del Usuario

11. 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 escape 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. 18. The pump must be
filled with liquid before it is started up again.
See fig. 16.
Fig. 18
Draining the pump

11.1 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.

11.2 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.
11.3 Start-up after a long period of
inactivity
The end cover incorporates a plug which can be
removed by means of a suitable tool. See fig. 19.
It is then possible to free the pump rotor if it has
seized up as a result of inactivity. If it has been
drained, the pump must be filled with liquid before
start-up. See fig. 16.
Fig. 19
Removing the end-cover plug

12. Service

If a pump has been used for a liquid
that is injurious to health or toxic, the
Note
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.
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