Danfoss VACON NX Commissioning And Maintenance Manual page 49

UNIT MAINTENANCE
Because the primary circuit is f
the heat exchanger clogs. Refer to the heat exchanger cleaning instructions found in the end of the
Commissioning and Maintenance folder that is supplied with the HX-unit.
If the liquid used in the secondary circuit contains biological or chemical residue, it is recommended
that a spare heat exchanger be stored locally. When the flow in the secondary circuit is too low, the
HX-unit should be shut down and the heat exchanger replaced. The dirty heat exchanger should be
needs to be changed.
The HX11 can, if needed, be removed without removing the HX-unit from the cubicle:
1. Drain both the primary circuit and the secondary circuit. The secondary circuit is drained
through the V163 valve (marked yellow in Figure 6.2-2). The primary circuit is drained
through the valves V301 and V302 (refer to the P&ID in Figure 4.2-2).
HXL120 AISI:
Disconnect the primary and secondary circuit connections
(marked violet in Figure 4.2-2) from the unit. The connections can
be opened with a box wrench.
HXL120 PVC-C:
The connections can be opened by hand, or if needed use an oil
filter remover (used to remove the oil filter from cars). Be
careful not to damage the connections.
2. Remove the one M8 nut from underneath the heat exchanger (marked
violet in Figure 6.2-3).
3. Carefully pull / lift / turn out the HX11 (Figure 6.2-4).
4.
instructions found in the end of the Commissioning and Maintenance folder that is supplied
with the HX-unit.
5. Connect the clean unit in reverse order using the instructions above. Add liquid and de-air
the unit according to the instructions in
Local contacts: http:/ / dr ives.danfoss.com/ danfoss- dr ives/ local - contacts/
chapter 5.1.6 and 5.1.7.
VACON 4 9
Figure 6.2-2
Figure 6.2-3
Figure 6.2-4
6