Maintenance By Component; Pump - Danfoss VACON NX Commissioning And Maintenance Manual

UNIT MAINTENANCE
6.2

MAINTENANCE BY COMPONENT

WARNING
!
NOTE

6.2.1 Pump

The pump PU11 (refer to the P&ID) does not require regular service. During the life cycle of the HX-
unit, it is likely that the shaft seal will have to be changed at some point. The shaft seal between the
pump housing and the motor is the most probable cause for leak on the centrifugal pump. When
changing the shaft seal, follow the pump maintenance rules in the pump service instructions found
in the Commissioning and Maintenance folder that is supplied with the HX-unit.
It is recommended that a reserve pump be stored locally in order to restore the operation quickly
when a pump needs to be maintained. There should also be a shaft seal in storage to facilitate
changing a broken or leaking shaft seal at site.
When the pump is leaking, remove the broken pump and replace it with a reserve pump. The broken
pump should be fixed immediately and stored for later use in case a similar pump failure occurs.
Purchase a new shaft seal from the unit manufacturer, and keep this in storage as well.
High-pressure hot coolant (6 bar, +60
cooling circuit. The coolant consists of liquid, propylene glycol and corrosion
WARNING
inhibitors, depending on the project. Glycol and corrosion inhibitors are
damaging for the eyes. If you get coolant in your eyes, on your skin, or in your
mouth, seek medical advice. Use safety goggl es.
HOT SURFACE
To change a pump:
1. Check that it is safe to turn off the drives connected to the HX-unit, and that there is enough
time reserved for the maintenance.
2. Prepare the HX-unit for liquid filling by connecting a hose to the filling valve (V161). Read
Chapter 5.1.7, Adding liquid and de-airing
3. Take the main drives connected to the HX-unit offline, according to the VACON
4. Shut down the power to the HX-
4.2-7.
Local contacts: http:/ / dr ives.danfoss.com/ danfoss- dr ives/ local - contacts/
Before maintenance shut off the electric power and the water supply to
the system. Make sure the system is cooled and not pressurised for
avoiding scalding and/or serious bodily injuries.
the HX-unit is in maintenance.
Tightening torques see Appendix 3 for PVC-C piping and Appendix 4 for
AISI304 piping.
before continuing.

C) may be present in the primary
VACON 4 7
®
NX Liquid
6