Maintenance And Service; Inspection; Dismantling The Pump; Oil Change - Grundfos SL1 Manual De Instrucciones

11. Maintenance and service

Warning
During maintenance and service, including
transportation to service workshop, always
support the pump by means of lifting chains or
place it in horizontal position to secure stability.
Warning
Before starting work on the pump, make sure that
the fuses have been removed or the mains switch
has been switched off. It must be ensured that
the power supply cannot be accidentally
switched on.
Make sure that all protective equipment has been
connected correctly.
Warning
Before starting work on the pump, make sure that
the mains switch has been locked in position 0.
All rotating parts must have stopped moving.
Warning
Maintenance work on explosion-proof pumps
must be carried out by FM approved service
FM
centres.
However, this does not apply to the hydraulic
components, such as pump housing, impeller,
etc.
Warning
FM
The cable must only be replaced by Grundfos or
a service workshop authorized by Grundfos.
Before carrying out maintenance and service, it must be ensured
that the pump has been thoroughly flushed with clean water.
Rinse the pump parts in water after dismantling.

11.1 Inspection

Pumps running normal operation should be inspected every
3000 operating hours or at least once a year. If the pumped liquid
is very muddy or sandy, inspect the pump at shorter intervals.
Check the following points:
• Power consumption
See pump nameplate.
• Oil level and oil condition
When the pump is new or after replacement of the shaft seal,
check the oil level and water content after one week of
operation. If there is more than 20 % extra liquid (water) in the
oil chamber, the shaft seal is defective. The oil should be
changed after 3000 operating hours or once a year. Use Shell
Ondina 919 oil or similar type. See section
• Cable entry
Make sure that the cable entry is watertight (visual inspection)
and that the cable is not sharply bent and/or pinched.
• Pump parts
Check impeller, pump housing, etc. for possible wear.
Replace defective parts. See section
pump housing and impeller.
• Ball bearings
Check the shaft for noisy or heavy operation (turn the shaft by
hand). Replace defective ball bearings. A general overhaul of
the pump is usually required in case of defective ball bearings
or poor motor function. This work must be carried out by
Grundfos or a service workshop authorized by Grundfos.
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•

11.2 Dismantling the pump

11.2.1 Oil change

After 3000 operating hours or once a year, change the oil in the
oil chamber as described below.
If the shaft seal has been replaced, the oil must be changed.
Draining of oil
1. Place the pump on a plane surface with one oil screw pointing
2. Place a suitable container (approx. 1 litre), for instance made
3. Remove the lower oil screw.
4. Remove the upper oil screw.
5. Clean the faces for the gaskets for oil screws.
11.2.1 Oil change.
11.2.2 Removing the
Warning
FM
Defective bearings may reduce the explosion
protection.
O-rings and similar parts
During service/replacement, it must be ensured that the
grooves for the O-rings as well as the seal faces have been
cleaned before the new parts are fitted. Grease O-rings and
recesses before assembly.
Note
Note
Do not reuse rubber parts.
Note
Note
See www.grundfos.us for service videos.
Warning
When loosening the screws of the oil chamber,
note that pressure may have built up in the
chamber. Do not remove the screws until the
pressure has been fully relieved.
downwards.
of transparent plastic material, under the oil screw.
Used oil must be disposed of in accordance with
Note
Note
local regulations.
If the pump has been in operation for a long period of time, if
the oil is drained off shortly after the pump has been stopped,
and if the oil is greyish white like milk, it contains water. If the
oil contains more than 20 % water, it is an indication that the
shaft seal is defective and must be replaced. If the shaft seal
is not replaced, the motor will be damaged.
If the quantity of oil is smaller than the quantity stated in
section quantities, the shaft seal is defective.
11.4 Oil