Perform Service - Grundfos DME Serie Instrucciones De Instalación Y Funcionamiento

8.3 Perform service

Only spare parts and accessories from Grundfos
should be used for maintenance. The usage of non-
original spare parts and accessories renders any
liability for resulting damages null and void.
Further information about carrying out maintenance
can be found in the service kit catalog on our
homepage (www.grundfos.com).
Warning
Risk of chemical burns!
When dosing dangerous media, observe
the corresponding precautions in the
safety data sheets!
Wear protective clothing (gloves and
goggles) when working on the dosing
head, connections or lines!
Do not allow any chemicals to leak from
the pump. Collect and dispose of all
chemicals correctly!
Before any work to the pump, the pump
must be disconnected from the power
Caution
supply. The system must be pressureless!
8.3.1 Dosing head overview
1
2
3
9
Fig. 27 Dosing head, exploded view (without
deaeration valve)
1 Safety diaphragm
2 Flange
3 Diaphragm
4 Valve on discharge side
5 Dosing head
6 Valve on suction side
7 Screws
8 Dosing head front plate (only PP, PVDF)
9 Drain opening
4
5
8
7
6
8.3.2 Dismantling the diaphragm and valves
Before dismantling, read section
breakage and section 8.5 Operation with loose
dosing head screws thoroughly.
Warning
Danger of explosion, if dosing liquid has
entered the pump housing!
If the diaphragm is possibly damaged or if
the pump was operated with damaged or
loose dosing head screws, don't connect
the pump to the power supply!
This section refers to fig. 27.
1. Make system pressureless.
2. Empty the dosing head before maintenance and
flush it, if necessary.
3. Take suitable steps to ensure that the returning
liquid is safely collected.
4. Dismantle suction, pressure and deaeration
hoses.
5. Unscrew deaeration valve.
6. Dismantle valves on suction and discharge side
(4, 6).
7. Loosen screws (7) on the dosing head (5).
8. Remove the screws, in case of PP or PVDF
dosing head together with the front plate (8).
9. Remove the dosing head (5).
10. Unscrew diaphragm (3) counter-clockwise and
remove it.
11. Make sure the drain opening (9) is not blocked or
soiled. Clean if necessary.
12. Check the safety diaphragm (1) for wear and
damage.
If nothing indicates that dosing liquid has entered the
pump housing, and if the safety diaphragm is not
worn or damaged, go on as described in section
8.3.3 Reassembling the diaphragm and
Otherwise proceed as described in section
8.4.1 Dosing liquid in the pump
8.4 Diaphragm
valves.
housing.
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